Good evening, what’s up? Does anyone have a lighting cart for the different stages?
differs based on types of lights
LED as a general rule
For seedlings, LED grow lights should generally be mounted between 24-36 inches above the plant canopy – however, this depends on the power (wattage) of the light source. Locate your LED grow lights at the furthest distance from the seedlings (~36”) – this keeps heat and light intensity levels lower and helps prevent seedlings from drying out. Once roots have been established and sprouting has started, the lights can be moved closer (usually within the first 2-3 weeks).
In the vegetative stage, [LED grow lights should be between 12-24 inches away from the top of the canopy. During this stage, more light is needed for photosynthesis, so the light source should be located closer to the plants.
As the plants progress through the flowering stage, their demand for intense light decreases. The top leaves of the canopy should be between 18-24 inches from the light source to produce flowers. It is at this stage that the plants increase in height and grow fruit. Depending on lights and how you want your crop to grow, it is not necessary to change the height of the lights during flowering, especially if you do not want taller plants.
How Far Should LED Grow Lights be from Seedlings?
At the very early stages of growth, seedlings are delicate and require less light intensity. This means you do not want to turn up the intensity too early as the seedlings will thrive with a far gentler approach. Depending on the size of the light, it is safe to keep grow lights located somewhere between 24-36 inches from the top of the soil.
How Far LED Grow Lights Should be From Clones
Cannabis cloning is a process where clippings or cuttings from a mature plant are used to grow another plant of the same kind. The LED grow light distance above the clones differs from the height required for seedlings. With clones, they will need intense light to begin. Depending on the power of the light and maturity of the plants, this could vary quite a bit between 14-36 inches from the top of the plant canopy.
How Far Should LED Grow Lights be for Flowering Plants
As plants grow, their needs change. Once the vegetative stage is complete, plants enter the bloom or “flowering” stage. For established plants, they are already where they need to be in order to thrive. During the flowering stage LED Grow lights should be located between 16-36 inches from the plant canopy. Moving the grow light closer will increase the light intensity which can maximize photosynthesis. However, if the grow lights are too close above plants, they can cause wider, more sprawling growth or can even damage the plant.
What about Other Stages of Growth? (H2)
Plants require different levels of light depending on each stage of growth. To understand exactly how far grow lights should be from plants, it is important to factor in the different stages of growth (2). It is also important to consider the power output of the grow light — this usually is related to the wattage of the light source, which is a primary factor in determining the optimal distance for LEDs when starting the growing process.
Plant growth can roughly be divided into three different stages – Seedling, Vegetative, and Flowering stages.
This means once healthy roots are firmly established, it’s time to increase the intensity and lower the lights.
Seedling Stage
During the initial stage as seedlings, LED grow lights should be placed higher up from the plants to avoid drying out the soil.
Some growers may be tempted to blast seedlings with a high-intensity light to promote faster growth, however, this will not help until the plants become established. Seedlings are too vulnerable in this early stage and require a gentler approach. Once plants mature, then higher light intensity is required to promote photosynthesis.
Vegetative Stage
During the vegetative stages, plants respond well to intense light – it is during this period that they are maturing and using photosynthesis to grow quickly. To increase the light intensity, LED grow lights should be located closer to the plant canopy. Strong, healthy stems and roots are key for a successful and repeatable yield.
While increasing light intensity promotes growth in the vegetative stage, it is important to closely monitor your plants, making sure to look out for adverse symptoms caused by too much light or not enough.
Flowering Stage
Flowering is the final stage of a plant’s growth cycle — during this time fruit production and stem growth accelerate. As plant growth transitions from the vegetative to the flowering or bloom stage, it is good practice to “phase” this transition process. To do this, gradually raise the height of the LED grow lights away from the plant canopy (using the height recommendations outlined earlier). Monitor the distance closely, keeping in mind the desired crop height and flowering needs for the specific plant/crop.
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As always, very informative information.
Thank you Mike.
I am sorry it is so convoluted. There are simpler answers but to do that,we need
Tent / room size, distance from canopy / tops of plants, type of light (lumens/ppfds /pmols/ etc)
normally, a decent led has a controller. We start at 30%, at around 18-24 inches…we increase strength as plant grows. Each stage gets an increase. 18" distance is usually for the life of the plant . 30% seedlings, 40-50% early veg, 60% late veg, 70% early flower up to 100% for full / late flower
Without a controller, 24-30 inches for seedlings, 18-24 for early veg, 16-18 for late veg, 12-18 for flower…
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Thank you Mike.
This is great information. The info for the veg stage is really helpful for me.
Hello Mike,
What would be the coolest temp out there for 3x3 ? I don’t want to keep running a mini split for that little grow space .
Thanks!
if you can maintain 60-85°f…that is all that is needed. 3x3 is easier to cool but can heat up if the light/s are too strong. I maintain a 2x3x3 for seedlings and a 2x3x5 for drying with only air coolers / frozen milk gallon jugs. I do lights on at night…I had a split (4 zones, 3k each zone) but electric bills were just too high. If you add some co2 (bags / mushroom growing) you can go from 85-90
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Good advice ! Had no clue about the shrooms (Exhale) ?