Cannabis cloning is a method used to create a new plant from a cutting taken from a healthy mother plant. This process allows growers to produce plants with the same genetics, growth traits, and chemical profile as the original. While cloning may seem simple, success depends on several environmental factors. One of the most important, and often misunderstood, factors is the light cycle. Light cycles play a major role in whether cannabis clones survive, develop roots, and grow into strong plants.
A light cycle refers to the number of hours of light and darkness a plant receives each day. For mature cannabis plants, light cycles control whether the plant stays in a vegetative state or begins flowering. Clones, however, are different. When a cutting is taken, it has no roots. This means it cannot absorb water or nutrients the way a normal plant can. During this early stage, the clone relies on stored energy and moisture in its leaves and stem. Because of this, lighting must be managed carefully to support rooting without causing stress.
Proper lighting helps clones maintain basic plant functions while they focus on forming new roots. Light provides energy for photosynthesis, which allows the clone to produce sugars needed for cell growth. However, too much light can be harmful. Strong or long-lasting light can cause clones to lose water faster than they can replace it. This leads to wilting, yellowing leaves, or even death. On the other hand, too little light can slow down growth and delay root development. Finding the right balance is key.
Clones also respond differently to light than established plants. Mature plants with roots can handle stronger light because they can pull water and nutrients from the growing medium. Clones cannot do this yet. Their light needs are lower, and their exposure must be gentle and consistent. This is why light cycles designed for flowering or late vegetative growth are not suitable for clones. Using the wrong light schedule can confuse the plant and reduce the chances of successful rooting.
Another important reason light cycles matter is plant stress. Stress weakens clones and makes them more likely to fail. Sudden changes in lighting, long periods of intense light, or irregular on-and-off schedules can all increase stress. When a clone is stressed, it may stop focusing on root development. Instead, it may try to protect itself by slowing growth or shedding leaves. In some cases, stress can lead to mold, disease, or poor long-term growth even if the clone survives.
Light cycles also influence plant hormones. Certain hormones help trigger root formation and cell repair. These hormones work best under stable, mild lighting conditions. When light exposure is too aggressive, hormone balance can be disrupted. This can delay rooting or result in weak, uneven roots. Proper light timing supports the natural processes that allow a cutting to heal and grow new tissue at the base of the stem.
It is also important to understand that light cycles do not work alone. Lighting interacts with humidity and temperature. Brighter or longer light periods increase heat and cause moisture to evaporate faster from the leaves. Since clones absorb moisture through their leaves until roots form, this can quickly dry them out. Managing light cycles helps control these environmental effects and keeps conditions stable during the most fragile stage of the clone’s life.
Many cloning failures happen not because of poor genetics or bad cuttings, but because of incorrect lighting. New growers often assume that more light means faster growth. With clones, this is not true. Gentle, well-timed light encourages steady rooting and healthier plants. Consistent light schedules also make it easier to transition clones into the vegetative stage later without shock or slowdown.
Understanding why light cycles matter gives growers a strong foundation for successful cannabis cloning. By using the right amount of light at the right time, clones can focus on forming roots, staying hydrated, and preparing for healthy growth. The sections that follow will explain exactly how to choose the best light cycle, how long lights should stay on, and how to avoid common lighting mistakes that reduce cloning success.
What Is the Ideal Light Cycle for Cannabis Clones?
The ideal light cycle for cannabis clones is one that supports root growth while keeping stress as low as possible. Unlike mature cannabis plants, clones do not have a developed root system when they are first cut. Because of this, their lighting needs are very different. Understanding how light cycles work during cloning helps improve survival rates and speeds up rooting.
Understanding Light Cycles in Simple Terms
A light cycle refers to how many hours of light and darkness a plant receives each day. This is usually written as two numbers, such as 18/6 or 24/0. The first number shows how many hours the lights are on. The second number shows how many hours the lights are off.
For cannabis clones, the goal is not to push fast top growth. The goal is to help the cutting stay alive long enough to grow roots. Light gives energy for basic plant functions, but too much light can cause stress, dehydration, and failure to root.
Common Light Cycles Used for Clones
The two most common light cycles used for cannabis clones are:
18/6 (18 hours of light, 6 hours of darkness)
This is the most widely recommended light cycle for clones. It provides plenty of light for energy while allowing a rest period. The dark hours give the plant time to slow down and recover from stress.
24/0 (24 hours of light, no darkness)
Some growers use constant light during the early rooting stage. This approach keeps photosynthesis running all day and night. While this can work, it is not always better and may increase stress in some setups.
Both cycles can be effective if other conditions such as humidity, temperature, and light intensity are well controlled.
Why Clones Do Not Need a Flowering Light Cycle
Cannabis clones should never be placed under a flowering light cycle such as 12/12. A flowering cycle signals the plant to focus on bud production instead of root and leaf growth. Clones need to stay in a vegetative state so they can form strong roots.
Short light cycles also reduce energy production. Since clones already struggle to take in water and nutrients without roots, reduced light hours can slow rooting or cause failure.
How Light Cycles Affect Root Development
Clones rely on stored energy in their leaves to survive. Light helps them produce more energy through photosynthesis, even before roots appear. However, more light also increases water loss through the leaves.
A balanced light cycle allows the clone to produce energy without losing too much moisture. This balance is critical because clones cannot replace lost water until roots form. That is why moderate light schedules are often more successful than extreme ones.
Light cycles also influence plant hormones. These hormones control cell growth and root formation. A stable and consistent light cycle helps maintain steady hormone levels, which supports faster and healthier rooting.
18/6 vs. 24/0: Which Is Better?
For most growers, an 18/6 light cycle is the safest and most reliable choice. The dark period helps reduce stress and allows the plant to carry out natural recovery processes. This cycle works well in both small and large cloning setups.
A 24/0 cycle can work in high-humidity environments where clones do not dry out easily. However, it increases the risk of leaf wilting if humidity drops or light intensity is too high. Continuous light also raises temperatures, which can further stress clones.
If problems like drooping, curling, or leaf yellowing appear, reducing light hours is often one of the first fixes.
Consistency Matters More Than Perfection
No matter which light cycle is chosen, consistency is very important. Light timers should be reliable and checked often. Sudden changes in light schedules can confuse the plant and slow root development.
Keeping the same light cycle from the first day of cloning until roots appear helps clones adjust and remain stable.
The ideal light cycle for cannabis clones is one that provides steady energy without causing stress. An 18/6 light cycle is the most commonly recommended because it balances light exposure with recovery time. A 24/0 cycle can work in controlled conditions but carries higher risk if other factors are not managed well.
Clones do not need flowering schedules, long dark periods, or intense light. They need gentle, consistent lighting that supports survival and root growth. By choosing the right light cycle and keeping it stable, growers can greatly improve cloning success and produce stronger, healthier plants.
Should Cannabis Clones Get 24 Hours of Light?
When growing cannabis clones, one common question is whether they should receive 24 hours of light per day or if they need a dark period. Understanding how clones respond to light helps growers choose a schedule that supports healthy rooting without causing stress.
Cannabis clones are cuttings taken from a mature plant. At this stage, they do not yet have roots. Because of this, clones behave differently from established plants. Their main goal is not fast leaf growth but root development and survival. Light plays a role in this process, but more light does not always mean better results.
Why Some Growers Use 24 Hours of Light
Many growers use a 24/0 light cycle, which means the clones receive constant light with no darkness. The main reason for this is consistency. Continuous light keeps the plant in a vegetative state and prevents any chance of flowering. This is important because flowering hormones can interfere with rooting.
Another reason is that clones rely on stored energy in their leaves. Light helps them continue photosynthesis at a low level, which provides energy while new roots form. With 24-hour light, clones can photosynthesize whenever they are able, without interruption.
Constant light can also help maintain stable temperatures in the grow area. Lights produce gentle warmth, which may help keep the environment within the ideal range for rooting, especially in cooler rooms.
Limits of 24-Hour Lighting
Even though 24-hour light is common, it is not always the best choice for every situation. Clones are sensitive. They lose water through their leaves, a process called transpiration. Too much light can increase this water loss. Since clones have no roots to replace lost water, they can wilt or dry out.
Plants also use darkness for internal recovery processes. During dark periods, plants slow down water loss and focus on repairing cells. Without any darkness, some clones may become stressed, especially if the light is too strong.
This is why light intensity matters more than total hours. A low-intensity light running 24 hours can be safer than a strong light running all day. Clones do not need bright light. In fact, bright light often does more harm than good during the rooting stage.
Comparing 24/0 and 18/6 Light Cycles
Another common option is an 18/6 light cycle, which means 18 hours of light and 6 hours of darkness. This schedule still keeps clones in the vegetative phase while giving them time to rest.
An 18/6 cycle can reduce stress by lowering heat and slowing water loss during the dark period. For some growers, this results in less wilting and healthier-looking clones. The dark period also allows the plant to complete natural respiration processes, which may support root formation.
Both light cycles can work. The difference often comes down to environmental control. In warm, dry rooms, 18/6 may be safer. In cool, stable environments with high humidity, 24/0 can work well when light intensity is kept low.
When to Choose One Over the Other
Choosing between 24 hours of light and 18/6 depends on several factors:
- Humidity: Higher humidity supports 24/0 lighting by reducing water loss.
- Temperature: If lights raise temperatures too much, a dark period helps cool the space.
- Light strength: Low-power lights are safer for longer schedules.
- Clone health: Fresh cuttings may benefit from less stress early on.
Many growers start with 24 hours of light during the first few days, then switch to 18/6 once clones show signs of stability, such as firm leaves and upright posture.
Important Things to Avoid
Regardless of the schedule, avoid sudden changes. Switching from 24/0 to 18/6 should be done carefully, using timers to keep light cycles consistent. Inconsistent lighting can confuse the plant and slow rooting.
It is also important not to combine 24-hour lighting with high heat or low humidity. This combination increases the risk of dehydration and failure.
Cannabis clones can survive and root under 24 hours of light, but this approach works best when light intensity is low and humidity is high. Continuous light helps maintain vegetative growth and provides steady energy, but it can also increase stress if conditions are not controlled. An 18/6 light cycle offers a balance by allowing recovery time while still supporting rooting. The best choice depends on the environment, light strength, and clone condition. Consistency, gentle lighting, and stable conditions matter more than the exact number of light hours.
How Many Hours of Light Do Clones Need Per Day?
Cannabis clones need light every day, but the number of hours matters more than many beginners realize. Clones are not like mature plants. They do not have roots yet, so they cannot absorb water and nutrients the same way. Because of this, light must be managed carefully to support rooting without causing stress.
Most cannabis clones do best with 18 to 24 hours of light per day. This range gives them enough energy to stay alive and begin forming roots, while limiting the risk of dehydration or shock.
Understanding Light Needs Before Roots Form
When a clone is first cut from a mother plant, it enters a survival stage. It can no longer pull water from the soil. Instead, it absorbs moisture through its leaves. Light helps keep basic plant functions running, but too much light can cause the clone to lose water faster than it can replace it.
This is why clones need gentle, long light exposure, not intense light for short periods. The goal is steady energy, not rapid growth.
Minimum Light Hours for Cannabis Clones
Most growers agree that 18 hours of light per day is the safe minimum for clones. At this level:
- The clone receives enough light to maintain photosynthesis
- The plant has a short dark period to rest
- Stress levels stay lower than with nonstop lighting
An 18/6 schedule (18 hours on, 6 hours off) works well in many environments, especially if temperature or humidity is harder to control.
Maximum Light Hours for Cannabis Clones
Some growers use 24 hours of light per day, especially during the first few days after taking cuttings. Continuous light can:
- Keep clones active and stable
- Prevent early stretching
- Support faster root initiation in some setups
However, 24 hours of light is not required for success. In some cases, it can increase stress if other conditions are not ideal.
How Light Hours Affect Clones Without Roots
Clones without roots cannot process light the same way rooted plants do. Light still triggers photosynthesis, but energy use must stay low. Long light hours work best when the light itself is soft.
If light hours are long but intensity is low:
- Leaves stay hydrated longer
- Transpiration stays under control
- Clones focus energy on forming roots, not growing leaves
If light hours are long and intensity is high:
- Leaves may wilt
- Edges may curl upward
- Clones may yellow or droop
This is why light duration and light strength must work together.
Balancing Light Exposure and Recovery Time
Clones also need time to recover from being cut. A short dark period allows plants to:
- Reduce moisture loss
- Slow respiration
- Repair damaged cells
This is one reason many growers prefer 18 hours of light instead of 24. The dark window gives clones a daily break without stopping root development.
If you notice clones looking weak or droopy, reducing light hours slightly can help. Moving from 24 hours to 18 hours often improves leaf posture and overall health within a few days.
Adjusting Light Hours During the Cloning Process
Light needs can change as clones develop:
- Days 1–3: 18–24 hours of gentle light is common
- Days 4–7: Maintain stable light hours while watching moisture levels
- After roots appear: Light hours can stay the same, but intensity may increase slowly
Consistency is more important than finding a perfect number. Sudden changes in light hours can stress clones and slow rooting.
Signs Light Hours Are Not Correct
Clones can show clear signs when light hours are off:
- Too many hours: wilting, dry leaf tips, curled leaves
- Too few hours: weak stems, pale leaves, slow rooting
Watching plant behavior is more useful than following a strict rule. Healthy clones should look firm, upright, and evenly colored.
Cannabis clones usually need 18 to 24 hours of light per day to root successfully. Eighteen hours offers a balanced approach with time for rest, while 24 hours can work when conditions are well controlled. Because clones do not have roots at first, long light hours must be paired with low light intensity and proper humidity. The key is consistency, gentle lighting, and careful observation. When light hours are managed correctly, clones stay hydrated, reduce stress, and develop roots more reliably.
What Type of Light Is Best for Cannabis Clones?
Choosing the right type of light is one of the most important steps when cloning cannabis. Clones are young cuttings with no roots, so their lighting needs are very different from mature plants. Strong or incorrect lighting can slow rooting, cause stress, or even kill clones. The goal is to provide gentle, steady light that supports leaf function while the cutting focuses on growing new roots.
Below is a clear breakdown of the best lighting options for cannabis clones and how each one affects rooting success.
Fluorescent Lights for Cannabis Clones
Fluorescent lights are one of the most popular choices for cloning. They produce soft light, low heat, and even coverage, which makes them ideal for fragile cuttings.
Common fluorescent options include:
- T5 fluorescent grow lights
- Standard shop lights with fluorescent tubes
- Compact fluorescent lights (CFLs)
These lights work well because clones do not need strong light. Fluorescent bulbs allow clones to absorb light without losing too much moisture through their leaves. Low heat also helps keep humidity stable, which is critical during the rooting stage.
Fluorescent lights can usually be placed close to clones without burning them. This helps provide consistent light across all cuttings. For small cloning setups, fluorescent lighting is often the easiest and most forgiving option.
LED Lights for Cannabis Clones
LED grow lights are becoming more common for cloning, especially low-power or dimmable models. LEDs are energy efficient and can provide the right spectrum for young plants, but they must be used carefully.
High-powered LEDs are not recommended for fresh clones. Strong LED light can cause stress because clones cannot replace water fast enough without roots. This can lead to wilting or leaf curl.
If using LEDs for clones:
- Choose low-wattage or seedling-specific LEDs
- Keep the light farther away than you would with fluorescent lights
- Use dimming features if available
LEDs with a higher blue-light output are better during cloning. Blue light supports leaf health and keeps growth compact while roots form.
CFL Lights for Small Clone Setups
Compact fluorescent lights (CFLs) are a good choice for small or beginner cloning setups. They are easy to find, inexpensive, and simple to use.
CFLs work best when:
- Used in small cloning domes or trays
- Positioned close but not touching the clones
- Paired with reflective surfaces to spread light evenly
While CFLs are not as powerful as other options, clones do not need high light levels. As long as light coverage is even, CFLs can support healthy rooting.
Why High-Intensity Lights Are Not Recommended
High-intensity lights such as metal halide (MH), high-pressure sodium (HPS), or strong full-power LEDs are not suitable for cannabis clones.
These lights produce too much:
- Heat
- Light intensity
- Stress on leaves
Without roots, clones cannot cool themselves or absorb water efficiently. Strong lighting increases transpiration, which dries out the cutting faster than it can recover. This often results in drooping leaves, burned tips, or slow root development.
High-intensity lights are best saved for vegetative or flowering stages after clones have established strong root systems.
Light Spectrum Considerations for Clones
The light spectrum plays an important role in clone health. During cloning, plants respond best to cooler light with more blue wavelengths.
Blue light helps:
- Maintain leaf structure
- Support photosynthesis without overstimulation
- Reduce stretching and stress
Full-spectrum lights can also work if they are not too strong. The key is keeping intensity low while providing steady exposure. Avoid red-heavy lighting, which is better suited for flowering plants.
Even Coverage and Light Placement
No matter which light type you choose, even coverage is critical. Uneven lighting can cause some clones to grow faster while others struggle.
To improve light coverage:
- Use reflectors or white walls
- Position lights evenly across the tray
- Avoid hotspots directly over single cuttings
Light should gently reach all clones without creating shadows or heat buildup.
The best light for cannabis clones is mentioning soft, low-heat, and consistent. Fluorescent lights and low-power LEDs are ideal because they protect clones while roots develop. High-intensity lights should be avoided during cloning, as they cause stress and dehydration. By choosing the right light type and spectrum, growers create a stable environment that supports faster rooting and healthier clones overall.
How Strong Should the Light Be for Cannabis Clones?
Light strength is one of the most important factors in successful cannabis cloning. Clones are young cuttings with no roots, so they cannot take in water and nutrients the same way a mature plant can. Because of this, they are very sensitive to strong light. Using the right light intensity helps clones stay healthy, reduce stress, and focus energy on growing roots.
Why Light Intensity Matters for Clones
Cannabis clones rely mostly on stored energy inside their leaves and stems. Until roots form, they cannot replace lost moisture fast enough. Strong light increases heat and causes faster water loss through the leaves. This can lead to wilting, leaf curl, or even clone death.
Low to moderate light intensity allows clones to photosynthesize gently without forcing them to lose too much moisture. The goal is to support slow, steady growth rather than fast top growth.
Recommended Light Intensity for Cannabis Clones
For most cannabis clones, light intensity should be kept low compared to vegetative or flowering plants.
- A general target range is 100–300 PPFD (photosynthetic photon flux density)
- Beginners should aim closer to 100–150 PPFD during the first few days
- Once clones look stable and upright, intensity can slowly increase
This level of light gives clones enough energy to stay alive and healthy without overwhelming them.
If you do not have a PPFD meter, you can still manage light strength by using distance and light type, which are explained below.
Signs the Light Is Too Strong
Too much light is one of the most common mistakes when cloning cannabis. Clones under excessive light often show clear warning signs:
- Leaves curl upward or look “taco-shaped”
- Leaf edges dry out or turn yellow
- Clones wilt even when humidity is high
- Growth stalls instead of improving
If you notice these signs, the light is likely too close or too powerful. Raising the light or dimming it usually solves the problem within a day or two.
Signs the Light Is Too Weak
While too much light is more dangerous, light that is too weak can also slow rooting.
Common signs of weak light include:
- Leaves drooping downward without wilting
- Pale green color over time
- Very slow or no visible progress after many days
Weak light does not usually kill clones, but it can delay root formation and reduce success rates. The goal is gentle light that keeps leaves firm and slightly lifted.
Recommended Distance Between Light and Clones
Light distance plays a big role in how strong the light feels to the clone.
General distance guidelines:
- Fluorescent or T5 lights: 12–24 inches above clones
- Low-power LEDs: 18–30 inches above clones
- Dimmable LEDs: Start at low power and increase slowly
If the light feels warm on the back of your hand at clone level, it is probably too strong. Clone lighting should feel cool or just slightly warm.
Why High-Intensity Lights Are Not Recommended
High-intensity grow lights are designed for rooted plants that can handle heat and strong light. Using these lights too early often causes stress and failure.
Strong lights increase:
- Leaf temperature
- Water loss
- Stress hormone production
Clones under intense light may look alive but fail to root. Lower light encourages the plant to focus on root growth instead of leaf defense.
How to Adjust Light Strength Safely
Adjusting light strength should be done slowly. Sudden changes can shock clones just as much as poor lighting.
Best practices include:
- Start with lower intensity during the first 3–5 days
- Increase light strength gradually once clones stay upright
- Watch leaves daily for changes in shape or color
- Adjust distance instead of changing light schedules
Using a timer and keeping lighting consistent helps clones settle into a stable environment.
Cannabis clones need gentle, controlled light to survive and root successfully. Light intensity should stay low to moderate, usually between 100 and 300 PPFD. Too much light causes stress, wilting, and slow rooting, while too little light can delay growth. Proper distance, cool temperatures, and gradual adjustments help clones stay healthy. By focusing on light strength instead of power, growers give clones the best chance to form strong roots and transition smoothly into the vegetative stage.
Does Light Spectrum Affect Clone Rooting Speed?
Yes, light spectrum plays an important role in how fast and how well cannabis clones develop roots. While light cycles control how long clones receive light, the light spectrum controls what kind of light energy the plant receives. This directly affects plant hormones, leaf behavior, and root formation during the early cloning stage.
Cannabis clones are different from mature plants because they do not have roots at first. They must survive by using stored energy in their leaves while slowly forming new roots. Because of this, the type of light used during cloning must support gentle growth without causing stress.
How light spectrum influences plant behavior
Light spectrum refers to the color range of light a plant receives. Different colors trigger different responses in plant cells. For clones, the goal is to encourage root development while keeping leaf growth slow and controlled.
Blue light is especially important during the cloning stage. It helps regulate plant hormones linked to vegetative growth and root formation. Blue light also keeps internodal spacing tight, meaning the clone stays compact instead of stretching.
Red light, while useful for flowering plants, is less helpful for clones. Too much red light can encourage stretching and leaf growth before roots are ready to support the plant. This can cause clones to weaken, wilt, or fail to root properly.
This is why many growers choose lights that are either blue-heavy or balanced toward the vegetative spectrum when rooting clones.
Blue light and rooting speed
Blue light supports faster and more stable root development in cannabis clones. It helps reduce water loss by slowing transpiration, which is important because clones cannot absorb water through roots yet. When transpiration is reduced, clones stay hydrated longer and experience less stress.
Blue light also helps maintain leaf structure and chlorophyll activity without forcing the plant to grow too quickly. This allows the clone to focus its energy on root creation rather than leaf expansion.
Clones grown under blue-dominant light often show:
- Less drooping or wilting
- Thicker stems
- Healthier leaf color
- More consistent root formation
These factors all contribute to faster rooting success and higher survival rates.
Using full-spectrum light for clones
Full-spectrum lights contain a mix of blue, red, and sometimes green wavelengths. These lights can be effective for clones as long as the intensity is kept low and the spectrum is not too red-heavy.
Full-spectrum lighting mimics natural sunlight, which helps maintain balanced plant functions. When used correctly, it can support both root formation and early vegetative health once roots begin to form.
However, full-spectrum lights designed for flowering are often too strong or too red for clones. If full-spectrum lights are used, they should be dimmed or placed farther away to prevent stress.
Many growers prefer vegetative LED lights or fluorescent lights because they naturally produce a softer, blue-leaning spectrum that is ideal for cloning.
How spectrum affects plant hormones
Light spectrum influences plant hormones such as auxins and cytokinins. These hormones control how plants grow and where they direct their energy.
Blue light helps balance hormone levels that support root initiation. It signals the plant to stay in a vegetative state and focus on structural development rather than reproduction.
If the light spectrum is too red or intense, hormone balance can shift. This may cause clones to stretch or focus on top growth instead of roots. When this happens, rooting slows down and failure rates increase.
By using the correct spectrum, growers help clones stay calm, hydrated, and focused on root development.
Avoiding spectrum-related stress
Even the right spectrum can cause problems if used incorrectly. Clones are sensitive, and too much light of any type can increase stress.
Signs that the spectrum or light setup may be wrong include:
- Curling or yellowing leaves
- Drooping even with proper humidity
- Slow or uneven root development
To avoid these issues, lights should be kept at a safe distance, and intensity should be low. Soft, diffused light works best during the cloning stage.
Light spectrum does affect how quickly cannabis clones develop roots. Blue-dominant light supports calm growth, reduces stress, and helps clones focus on rooting. Full-spectrum lights can work if intensity and distance are controlled, but red-heavy or high-power lights can slow rooting and harm clones. By choosing the right spectrum and keeping light gentle, growers can improve rooting speed, clone health, and overall success during the cloning process.
Can Too Much Light Kill Cannabis Clones?
Yes, too much light can damage or even kill cannabis clones, especially during the early rooting stage. Clones are young cuttings with no root system or only very small roots. Because of this, they cannot handle light the same way mature plants can. Understanding how excess light affects clones is key to improving survival and rooting success.
Why Cannabis Clones Are Sensitive to Light
Cannabis clones rely on stored energy in their leaves while they grow new roots. Since they cannot absorb water and nutrients from the growing medium yet, they are very sensitive to stress. Strong or excessive light increases the plant’s need for water through a process called transpiration. When clones lose water faster than they can replace it, they wilt, weaken, and may die.
Unlike established plants, clones cannot cool themselves well. Bright lights raise leaf temperature and speed up moisture loss. This is why lighting that works for vegetative plants is often too intense for clones.
Common Symptoms of Light Stress in Clones
Recognizing light stress early can help prevent permanent damage. The most common signs include:
- Wilting or drooping leaves even when humidity is high
- Leaf curling, especially upward at the edges
- Yellowing or bleaching of leaf surfaces
- Dry or crispy leaf tips
- Slow or stalled root development
These symptoms often appear within the first few days if lighting is too strong or too close. Many growers mistake these signs for nutrient problems, but clones do not need nutrients until roots form. In most cases, the real issue is excessive light.
How Too Much Light Dries Out Clones
Light directly affects how fast a plant loses moisture. Strong light causes leaves to open their stomata, which releases water vapor. Since clones cannot pull water from roots, they rely on humidity in the air and moisture stored in their leaves.
High-intensity light increases transpiration faster than humidity can replace moisture. Even in a humidity dome, too much light can overwhelm the clone’s ability to stay hydrated. This leads to limp stems, weak leaves, and eventual failure to root.
Light Distance and Intensity Problems
Clones are often damaged because the light is too close or too powerful. High-output LEDs, HID lights, or strong full-spectrum grow lights can easily overwhelm clones if not adjusted correctly.
If lights are placed too close:
- Leaf temperature rises quickly
- Moisture loss increases
- Stress hormones increase, slowing root growth
If lights are too intense:
- Clones focus energy on survival instead of rooting
- Leaves may bleach or burn
- Rooting time becomes longer or fails completely
Low to moderate light intensity is best during the first 7–14 days of cloning.
Preventing Light Stress During Cloning
To avoid killing clones with too much light, follow these basic principles:
- Use low-intensity lighting such as fluorescent or dimmed LED lights
- Keep lights farther away than you would for vegetative plants
- Avoid direct overhead heat from strong fixtures
- Maintain high humidity to reduce moisture loss
- Use consistent light cycles without sudden changes
Clones do better with gentle, even light that supports slow photosynthesis without stress. The goal is root growth, not rapid leaf growth.
Balancing Light With Environment
Light does not work alone. Temperature and humidity interact with lighting levels. Strong light increases heat, which increases water loss. If humidity is too low, clones dry out faster under bright light.
A stable environment helps clones tolerate light better. When humidity and temperature are controlled, clones can handle moderate lighting without stress. If environmental control is limited, reducing light intensity is the safest option.
Too much light is a common cause of cloning failure. Cannabis clones are fragile and cannot handle strong or intense lighting until roots form. Excess light increases moisture loss, causes stress, and slows or stops root development. By using gentle light, proper distance, and stable environmental conditions, growers can greatly improve clone survival and rooting success. Keeping light levels low during the early stage allows clones to focus on building healthy roots instead of fighting stress.
Should Light Cycles Change After Clones Root?
Yes, light cycles should change after cannabis clones develop roots. This change is important because rooted clones have different needs than unrooted cuttings. Once roots appear, the plant can absorb water and nutrients more efficiently. This allows it to handle stronger light and a more structured growth schedule. Adjusting the light cycle at the right time helps clones grow faster, stay healthy, and prepare for transplanting.
How to Tell When Clones Are Ready for a Light Change
Before changing the light cycle, it is important to confirm that the clones are fully rooted. Signs of successful rooting include new leaf growth, stronger stems, and resistance when gently tugged. Roots may also be visible at the bottom of plugs, cubes, or pots. If clones still look limp or pale, they may not be ready for changes yet. Switching light conditions too early can stress the plant and slow growth.
Transitioning From Rooting to Vegetative Light Cycles
During the rooting phase, clones are often kept under 18 to 24 hours of light with low intensity. After roots form, growers usually move clones into a standard vegetative light cycle. The most common option is an 18 hours on and 6 hours off schedule. This cycle gives plants time to rest while still supporting strong vegetative growth.
Some growers keep clones under 24 hours of light for a short time after rooting. This can work, but it is not required. Adding a dark period helps regulate plant processes and reduces stress. Darkness allows plants to complete respiration and energy repair cycles, which supports stronger long-term growth.
Increasing Light Intensity Gradually
Rooted clones can handle more light than unrooted ones, but changes should be slow. Light intensity should be increased in small steps over several days. Sudden exposure to strong light can cause leaf curl, bleaching, or wilting. This happens because young roots may not yet support high water demand.
A good approach is to keep the same light source but lower it gradually, or increase brightness if using dimmable LEDs. Watch how the plant responds. Healthy signs include upright leaves, even color, and steady growth. If leaves droop or turn pale, reduce intensity and give the plant time to adjust.
Adjusting Light Distance After Rooting
Distance between the light and the plant also matters. During cloning, lights are usually placed farther away to avoid stress. After rooting, lights can be moved closer. This increases energy for leaf and stem growth. The correct distance depends on the type of light used, but changes should be slow and controlled.
Start by reducing the distance slightly and observe the plant for 24 hours. If no stress appears, the light can be moved closer again. This gradual method helps clones adapt without shock.
Preparing Clones for Transplanting
Proper light adjustments help clones prepare for transplanting into larger containers or new environments. Strong light encourages thicker stems and better leaf development. These traits help clones survive transplant stress.
If clones will be moved to a different grow space, it helps to match the light schedule ahead of time. For example, if the vegetative room uses an 18/6 cycle, clones should already be on that schedule before moving. This reduces stress and keeps growth consistent.
Avoiding Common Mistakes After Rooting
One common mistake is keeping clones under weak light for too long after rooting. This can cause stretching and slow growth. Another mistake is increasing light too fast, which can damage young leaves. Inconsistent light schedules can also confuse plant growth patterns and slow development.
Using a timer helps keep light cycles steady. Consistency is more important than intensity at this stage. Plants respond best to predictable conditions.
Once cannabis clones develop roots, their light needs change. Moving from a gentle rooting setup to a vegetative light cycle supports faster and healthier growth. The key is to make changes slowly. Gradually increase light intensity, adjust distance carefully, and introduce a consistent light schedule with a dark period. These steps help clones grow stronger, reduce stress, and prepare for transplanting. Proper light management at this stage builds a solid foundation for the rest of the plant’s life cycle.
How Does Light Cycle Interact With Humidity and Temperature?
Light, humidity, and temperature work together during the cloning stage. If one is off, the others can cause problems. Cannabis clones are very sensitive because they do not have roots yet. They cannot pull water from the growing medium. Instead, they rely on moisture in the air and careful control of heat and light. Understanding how these factors interact helps improve rooting success and reduces plant stress.
Light affects heat and moisture loss.
When lights are on, they produce heat. Even low-intensity lights raise the temperature around clones. Warmer air causes plants to lose water faster through their leaves. This process is called transpiration. Since clones have no roots, too much transpiration can cause wilting or leaf damage. The longer the light cycle, the longer clones are exposed to heat and moisture loss.
Humidity helps clones stay hydrated.
High humidity is important during cloning. Most growers aim for 70% to 85% humidity in the first few days. High humidity slows water loss from leaves. This allows clones to stay firm and healthy while they form roots. If humidity is too low, light exposure can dry out clones quickly, even if the light is not very strong.
Light intensity changes humidity needs.
Stronger light increases transpiration. If light intensity goes up, humidity often needs to go up as well. For example, if clones are under bright LEDs, humidity must be carefully controlled. If humidity is too low, leaves may curl, droop, or turn yellow. Using softer lighting, such as fluorescent or low-power LEDs, helps keep moisture loss under control.
Temperature is closely linked to lighting.
Lights raise air temperature, especially in small spaces like clone tents or domes. The ideal temperature range for cannabis clones is usually between 72°F and 78°F (22°C to 26°C). Temperatures above this range can stress clones and increase water loss. Temperatures below this range can slow root development. The light cycle should support stable temperatures, not cause spikes.
Long light cycles increase heat buildup.
Using a 24-hour light cycle means lights never turn off. This can cause steady heat buildup, especially if ventilation is limited. In warm climates or small grow areas, this may push temperatures too high. In these cases, an 18/6 light cycle can help. The dark period allows the area to cool down and gives clones time to recover.
Dark periods can help balance the environment.
A short dark period lowers temperature and reduces transpiration. This helps clones retain moisture. Darkness also allows plants to focus on internal processes, such as cell repair and hormone balance. While clones can root under constant light, many growers find that a small dark period helps stabilize humidity and temperature.
Humidity domes and lighting must work together.
Humidity domes are commonly used during cloning. They trap moisture and create a stable environment. However, lights can heat the air inside the dome quickly. If the dome becomes too warm, humidity can drop suddenly when vents are opened. It is important to monitor conditions inside the dome, not just the room.
Different climates require different light adjustments.
In dry climates, light intensity and duration may need to be reduced to prevent dehydration. In humid climates, airflow becomes more important to prevent mold. In cooler climates, slightly longer light cycles may help maintain warmth. Light cycles should always be adjusted based on how they affect temperature and humidity together.
Monitoring is key to success.
Using simple tools like a thermometer and hygrometer helps track conditions. These tools show how lights affect the environment throughout the day. If temperature rises too much during the light period, lowering light intensity or shortening the light cycle can help. If humidity drops too fast, misting or using a dome may be needed.
Consistency matters more than extremes.
Clones respond best to stable conditions. Sudden changes in light, temperature, or humidity can shock young cuttings. Keeping the light cycle consistent helps maintain steady environmental conditions. Timers are useful for keeping light schedules regular and predictable.
Light cycles do more than control plant growth. They directly affect temperature and humidity in the cloning area. Longer or stronger light increases heat and moisture loss, which can stress clones without roots. High humidity helps protect clones, while stable temperatures support faster rooting. By balancing light duration, light intensity, humidity, and temperature, growers can create a safe environment where cannabis clones stay healthy and develop strong roots.
Do Cannabis Clones Need Darkness to Root Properly?
Cannabis clones can root successfully with or without periods of darkness, but understanding how darkness affects young cuttings helps growers choose the best light cycle. Clones are different from mature plants. They do not yet have roots, so they rely on stored energy in their leaves and stems. Light and darkness both play a role in how clones manage stress, recover from cutting, and form new roots.
Darkness does not directly cause roots to grow. Roots form because of internal plant hormones, moisture balance, and healthy cell activity. However, darkness can support these processes in indirect ways. When lights are off, clones slow down water loss and metabolic activity. This rest period can help them recover from stress, especially in the first few days after cutting.
During darkness, plants focus more on respiration rather than photosynthesis. Respiration is how plants convert stored sugars into usable energy. For clones, this energy is important because it supports cell repair and root initiation. Since clones cannot pull water or nutrients from soil yet, reducing stress is critical. Darkness helps limit excess transpiration, which is the loss of water through leaves.
Some growers use a 24-hour light cycle during cloning, while others prefer 18 hours of light and 6 hours of darkness. Both approaches can work. Continuous light provides more time for photosynthesis, which can help maintain leaf health. However, too much light can also increase heat and water loss. Without roots, clones can dry out quickly under strong or nonstop lighting.
An 18/6 light cycle includes a daily dark period. This dark time allows clones to slow down and conserve moisture. It can also help prevent light stress, especially when humidity is not perfectly controlled. In environments where temperature and humidity are stable, clones may do well with 24 hours of light. In less controlled spaces, a short dark period often improves survival rates.
Darkness also supports hormone balance. Plant hormones like auxins are important for root development. These hormones move through the plant during both light and dark periods. Darkness does not increase hormone levels on its own, but it helps prevent stress that can disrupt hormone movement. A calm, low-stress clone environment allows hormones to do their job more effectively.
Another benefit of darkness is leaf recovery. After being cut from a mother plant, clones experience shock. Leaves may droop or curl as the plant adjusts. Darkness reduces the demand placed on the leaves. This gives cells time to repair damage caused by cutting. Once the clone stabilizes, light can again support growth without causing strain.
It is important to understand that clones do not need long periods of darkness like flowering plants do. They should never be placed on a 12/12 cycle during rooting. That schedule signals flowering and can confuse the plant. Clones are still in a vegetative state and need longer light exposure to stay healthy.
The best approach is balance. Light provides energy, while darkness supports recovery. Many growers find that 18 hours of light and 6 hours of darkness offers a good mix of both. This schedule reduces stress, limits dehydration, and still provides enough light to keep leaves green and active.
Environmental conditions matter as much as light timing. If humidity is high and temperatures are moderate, clones can handle more light. If air is dry or warm, darkness becomes more helpful. Growers should watch how clones respond. Signs that clones need more rest include wilting, curled leaves, or dry leaf edges.
Darkness should always be consistent. Irregular light schedules can stress clones and slow rooting. Using a timer helps keep light and dark periods stable. Consistency allows the plant to adjust and focus energy on root formation instead of stress response.
Cannabis clones do not require darkness to root, but short dark periods can support the process. Darkness helps reduce stress, conserve moisture, and support recovery after cutting. While clones can survive under 24-hour light, many benefit from a balanced light cycle that includes rest. The key is gentle lighting, stable conditions, and consistency. When light and darkness work together, clones are more likely to root successfully and grow into healthy plants.
Common Light Cycle Mistakes When Cloning Cannabis
Lighting mistakes are one of the main reasons cannabis clones fail to root or die early. Clones are very sensitive during this stage because they do not yet have roots. They depend on stored energy and moisture in their leaves and stems. Even small lighting errors can cause stress, slow rooting, or complete failure. Below are the most common light cycle mistakes growers make when cloning cannabis, along with clear explanations of why these mistakes matter.
Using a Flowering Light Schedule Too Early
One of the biggest mistakes is using a flowering light cycle, such as 12 hours of light and 12 hours of darkness. This schedule is designed for mature plants that are ready to produce buds, not for fresh clones.
Clones need light to stay in a vegetative state while they focus on root development. When clones are placed under a flowering schedule, they can become confused and stressed. This stress slows down root growth and may cause yellowing, drooping, or weak stems. In some cases, clones may fail to root at all.
For best results, clones should be kept under a vegetative light cycle, usually 18 to 24 hours of light per day. This keeps their growth signals stable and supports faster rooting.
Providing Light That Is Too Strong
Another common mistake is using lights that are too intense. High-powered grow lights are great for flowering plants, but they are not suitable for clones.
Strong light causes clones to lose moisture too quickly through their leaves. Since clones do not have roots yet, they cannot replace this lost water. This leads to wilting, curling leaves, and leaf burn. Many growers mistake this damage for nutrient problems, when the real issue is excessive light.
Clones need gentle light. Low-intensity LEDs, fluorescent lights, or T5 fixtures are usually enough. The goal is to provide light without heat or stress. If the leaves look pale, crispy, or droopy, the light is likely too strong or too close.
Placing Lights Too Close to Clones
Even low-wattage lights can cause problems if they are placed too close. When lights are too near, clones may show signs of heat stress or dehydration.
Common symptoms include:
- Leaves pointing downward
- Dry leaf edges
- Wilting shortly after lights turn on
Proper distance allows light to spread evenly and keeps heat away from the clones. Many growers rush this step and place lights close to speed up growth, but this usually has the opposite effect. A small gap between the light and the canopy helps protect clones while they form roots.
Placing Lights Too Far Away
While too much light is harmful, too little light also causes problems. Lights that are too far away may not provide enough energy for clones to stay healthy.
When clones receive weak light, they may stretch, become thin, or grow slowly. Leaves may droop or turn yellow as the plant struggles to produce enough energy. This can delay rooting and weaken the clone before it is ready for transplant.
Balanced light distance is key. The light should be close enough to support photosynthesis but far enough to avoid stress.
Inconsistent Light Cycles
Inconsistent lighting is another major mistake. Turning lights on and off at different times each day can confuse clones and disrupt their internal processes.
Plants rely on stable light patterns to regulate growth and recovery. Irregular light cycles can increase stress and slow root development. This often happens when growers forget to use timers or adjust lights manually.
Using a reliable timer helps maintain consistency. Even small changes in light timing can affect clone success, especially during the first 7 to 14 days.
Changing Light Cycles Too Quickly
Some growers change light cycles too fast after clones root. For example, switching immediately from low light to strong vegetative lighting can shock young plants.
Once roots appear, clones still need time to adjust. A sudden increase in light intensity or duration can stress the plant and slow its transition into healthy vegetative growth.
Light changes should be gradual. Increasing light strength slowly allows clones to adapt without stress.
Ignoring the Relationship Between Light and Environment
Light does not work alone. Stronger light increases heat and water loss. Many growers focus only on light hours and forget how lighting affects temperature and humidity.
If light intensity increases but humidity stays low, clones may dry out quickly. This mistake often leads to failed rooting even when the light schedule looks correct.
Light settings should always match the environment. Gentle light works best when combined with warm temperatures and high humidity.
Most cloning failures are caused by simple lighting mistakes. Using flowering schedules, strong lights, incorrect distances, or inconsistent timing can slow rooting or kill clones. Clones need gentle, steady light and stable cycles to succeed. By avoiding these common errors and keeping lighting simple and consistent, growers can greatly improve cloning success and produce healthier, stronger plants.
Light Cycle Setup Checklist for Successful Cannabis Cloning
Setting up the correct light cycle for cannabis clones does not need to be complicated. A clear checklist helps reduce mistakes and improves rooting success. This section explains each part of the light cycle setup in simple steps, from choosing the right light to making small adjustments as clones develop.
Choose the right type of light
Clones need gentle light. They do not have roots yet, so they cannot handle strong lighting. Fluorescent lights, low-watt LEDs, or T5 grow lights work well. These lights produce less heat and spread light evenly. Avoid high-powered grow lights meant for flowering plants. Strong light can stress clones and cause wilting.
Select the correct light spectrum
Blue or cool-white light supports early growth and rooting. Full-spectrum lights also work well if they are not too intense. The goal is to support leaf health without forcing fast growth. Strong red-heavy light is not needed at this stage and can increase stress.
Set the proper light cycle schedule
Most growers use either 18 hours of light and 6 hours of darkness (18/6) or 24 hours of light (24/0). Both schedules can work. If using 24/0, make sure the light is very gentle. If using 18/6, the dark period helps reduce stress and heat. Choose one schedule and keep it consistent.
Use a reliable timer
A timer keeps the light cycle steady. Inconsistent lighting confuses plants and slows rooting. Digital timers are often more accurate than manual ones. Check the timer regularly to make sure it works correctly and does not skip cycles.
Set the correct light distance
Place lights far enough away to avoid stress but close enough to support photosynthesis. For fluorescent or low-power LED lights, this is usually 12 to 24 inches above the clones. If leaves curl, bleach, or dry out, the light may be too close. If clones stretch or lean upward, the light may be too far away.
Control light intensity
Clones do not need bright light. Soft, even lighting is best. If your light has adjustable power, use the lowest setting. If not, raise the light higher. Strong light increases water loss through the leaves, which is dangerous for clones without roots.
Manage heat from lighting
Lights produce heat, even low-power ones. Heat increases water loss and stress. Keep the grow area cool but not cold. Ideal temperatures are usually between 72°F and 78°F (22°C to 26°C). If the area feels warm to your hand at plant level, raise the light or improve airflow.
Match lighting with humidity levels
Light, heat, and humidity work together. Bright light increases transpiration. High humidity helps clones survive while roots form. Many growers aim for 70% to 85% humidity during early cloning. If humidity is low, reduce light intensity to prevent wilting.
Keep lighting consistent day to day
Avoid changing the light schedule or intensity often. Clones respond best to stable conditions. Sudden changes can slow rooting or cause stress. Make small adjustments only when needed, and wait a few days to see results.
Observe clones daily
Use the plants as your guide. Healthy clones have firm leaves and steady color. Drooping, yellowing, or crispy edges may point to light problems. Adjust distance or hours slowly rather than making large changes all at once.
Prepare for the rooting transition
Once roots appear, clones can handle slightly more light. Do not increase intensity suddenly. Lower the light gradually or increase brightness over several days. This helps clones adjust without shock.
Keep the setup clean and simple
Clean light fixtures and covers regularly. Dust can block light and change intensity. Avoid clutter in the cloning area so light spreads evenly across all plants.
A successful light cycle setup for cannabis cloning focuses on gentle light, stable timing, and careful observation. Use low-intensity lighting, keep schedules consistent, manage heat and humidity, and make slow adjustments as clones develop. When lighting is balanced and steady, clones can focus on forming strong roots, which leads to healthier plants later in the grow cycle.
Conclusion: Optimizing Light Cycles for Strong, Healthy Cannabis Clones
Proper light cycles play a major role in the success of cannabis cloning. From the moment a cutting is taken, light affects how well the clone manages stress, holds moisture, and begins forming new roots. Unlike mature plants, clones cannot rely on an established root system, so lighting must support gentle growth without overwhelming the plant. When light cycles are set up correctly, clones stay healthy, root faster, and have a higher chance of surviving the transplant stage.
One of the most important points to remember is that cannabis clones do not need a flowering light cycle. Short day cycles meant for flowering can confuse clones and slow down root development. Instead, clones respond best to longer light periods that support vegetative growth. Many growers use either an 18-hours-on and 6-hours-off cycle or a full 24 hours of light. Both can work when managed correctly. Continuous light can encourage steady energy production, while a short dark period can help plants rest and recover. The key is consistency. Sudden changes or irregular schedules can stress clones and reduce success rates.
Light intensity is just as important as light duration. Clones need soft, low-intensity light because they cannot absorb large amounts of energy without roots. Strong lights placed too close can cause wilting, leaf curl, or dryness. Weak or distant lights, on the other hand, can slow growth and delay rooting. Keeping lights at the correct distance and adjusting them as clones develop helps prevent these issues. Gentle lighting allows clones to focus on root formation rather than trying to support heavy leaf growth.
Light spectrum also plays a role in rooting success. Blue and full-spectrum light encourage vegetative growth and help clones stay compact and healthy. These light types support leaf function without pushing the plant too hard. High-intensity red-heavy light is better suited for flowering plants and should be avoided during cloning. Using the right spectrum helps balance growth and reduces stress during the early stages.
It is also important to understand how lighting interacts with temperature and humidity. Light produces heat, and too much heat can increase water loss from leaves. Since clones take in water through their leaves before roots form, high heat combined with strong light can cause rapid dehydration. Proper lighting works best when paired with stable humidity and moderate temperatures. This balance helps clones stay hydrated while roots develop.
As soon as clones show healthy root growth, lighting needs begin to change. Rooted clones can handle stronger light and may need adjustments in both intensity and distance. Making these changes slowly helps avoid shock. Gradual transitions prepare clones for transplanting and future vegetative growth under stronger lighting conditions.
Many cloning problems can be traced back to simple lighting mistakes. Using flowering schedules, placing lights too close, or failing to use timers often leads to stress and poor rooting. Avoiding these common errors and following proven light cycle guidelines can greatly improve results. A reliable setup with consistent timing, proper intensity, and the right spectrum creates a stable environment for clones to thrive.
In summary, successful cannabis cloning depends heavily on proper light cycles. Long, consistent light periods support early growth, while gentle intensity protects fragile cuttings. The right spectrum encourages healthy development, and balanced environmental conditions prevent dehydration and stress. By paying close attention to lighting from start to finish, growers can increase rooting success, reduce losses, and produce strong, healthy clones ready for the next stage of growth.
Research Citations
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Moher, M., Llewellyn, D., Golem, S., Foley, E., Dinka, S., & Jones, M. (2023). Light spectra have minimal effects on rooting and vegetative growth responses of clonal cannabis cuttings. HortScience, 58(2), 215–221.
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Questions and Answers
Q1: What is a light cycle for clones?
A light cycle for clones is the schedule of light and darkness they receive each day, usually measured in hours of light per 24-hour period.
Q2: What is the best light cycle for plant clones?
The most common and effective light cycle for clones is 18 hours of light and 6 hours of darkness (18/6), which supports rooting while allowing rest.
Q3: Can clones stay under 24 hours of light?
Yes, clones can survive under 24 hours of light, but continuous light may cause stress and is usually unnecessary for successful rooting.
Q4: Why do clones need darkness in their light cycle?
Darkness allows clones to rest and carry out important metabolic processes that support root development and overall health.
Q5: When should the light cycle start after taking a clone?
The light cycle should begin immediately after the clone is placed in its growing environment to help maintain stable growth conditions.
Q6: Does light intensity matter more than light cycle for clones?
Both matter, but light intensity should be low to moderate, as clones need gentle light while developing roots, regardless of the cycle used.
Q7: How long should clones stay on a cloning light cycle?
Clones typically stay on an 18/6 light cycle until they have established healthy roots, which usually takes 7 to 14 days.
Q8: Can clones flower if the light cycle is wrong?
Clones usually do not flower during early stages, but extended darkness or flowering light cycles can confuse the plant once roots form.
Q9: Is the light cycle different for clones compared to mature plants?
Yes, clones require longer light periods and lower intensity compared to mature plants, which may use different cycles for growth or flowering.
Q10: Should the light cycle change once clones are rooted?
Yes, once clones are fully rooted, they can be gradually transitioned to the light cycle used for vegetative growth.
