If you are just getting started growing cannabis you will need to start your cannabis seeds and get them out of the ground. Once you do that you are ready to provide the best lighting for cannabis seeds. There are thousands of types of growing lights out there right now, how do you know which ones you need to use to get the best start for your cannabis seeds?
Starting Cannabis Seeds
Needless to say, cannabis seeds don’t need any light until they come out of the ground. When this happens it is very important that they have access to an adequate lighting source. If the cannabis seedling doesn’t have a good light supply it will stretch, grow leggy and be more susceptible to Botrytis (Cannabis Mold). This mold will attack the base of the stem of the seedling, killing it in a day or two.
Once the plant is growing, good lighting is one of the most important factors for your seedling as it will start the process of photosynthesis that gets the plant growing.
What is the Best Lighting for Cannabis Seeds
While you can use just about any high powered light for growing cannabis seedlings, some will work better then others. With seedling it is important to give them the best start possible to get a healthy vegetative cannabis plant.
HID Lighting (High Intensity Discharge)
Unless you have a smaller one that you are able to dim HID lighting is overkill for cannabis seedlings. If you use a 400 watt HID Metal Halide light and dim it down to 50% to 75% this would work well for lighting cannabis seedlings. Growers can buy these lights in 400, 600 and 1000 watts. The two larger lights would work fine for starting seedlings, seedlings ready don’t need that kind of power when they first emerge from the soil.
T5 Fluorescent Bulbs
These bulbs have been around for many years in the cannabis growing industry. They have been used for many years to start growing cannabis, supplemental lighting and for seedlings.
T5 bulbs are easy to find at any gardening store, hardware store. They are easy to hook up, and provide the perfect amount of lighting for young cannabis seedlings.
You can use T5 bulbs for the first month of seedling growth and into the vegetative stage of growing. Keep these bulbs about 12 to 24 inches above the growing cannabis seedlings. They are much cheaper to run for electricity than HID lighting thereby saving you money for more powerful lighting in flowers.
These bulbs come in different types relating to if they are “cool” or “warm”. The warm types are more orange in color while the cool bulb types are more blue in color. For starting seedlings we recommend the blue or cool type bulbs.
LED Lighting for Cannabis Seedlings
LED lights are a great choice for getting a strong start for your young cannabis plants; they use very little energy, have a perfect spectrum, and are very bright. Buying LEDs that are dimmable are even more efficient as you can dim them from seedling to flowering saving energy the whole growing cycle.
Are LED lights ok for Seedlings?
Yes, LED lights work great to grow and start cannabis seedlings. We recommend them over any other types of lighting for seedlings. They have a great lighting spectrum and will help to keep your seedlings short, so they will not fall over stretching for more light.
How Far should the LED be from seedlings?
With any growing light you never want to burn the top of the plants, this goes for seedlings as well. Young cannabis seedlings are much more tender than mature cannabis plants. Heat and very hot bright lights will have more of a negative effect on seedlings. When hanging your seedling LED you will want to keep it about 15 to 18 inches above the cannabis plant.
Never put your grow lighting too close to the top of your seedlings. As you seedlings get more sets of leaves, grow taller, and have a stronger stem you can undim the lighting more, or move the lighting closer to the plants.
Should I dim my LED grow Lights for seedlings?
There is no reason you have to dim your LED grow lighting for seedlings. However the seedlings probably don’t need that much light, and therefore you are wasting energy that the seedlings don’t need. We recommend that you dim the LEDs for the first couple of weeks after the cannabis seed comes out of the ground.
How long should grow lights be on for Seedlings?
Growers LED lights should be on at least 16 hours per day with 8 hours of darkness. There is however no maximum and you can run lighting for seedlings for 24 hours per day if you wish. This will speed up growth of the plant over 16 hours per day for the best lighting for cannabis seeds.
How do I know if my seedlings are getting too much light?
The seedlings will start to lose color in their young leaves and they will have a more whitish color instead of a dark green color. The main seedling stem will also start to droop down and may fall over.
Can I leave my grow light on 24 hours for seedlings?
Cannabis Seedlings can have the lighting on 24 hours a day this will speed up the growing process and have no negative effects on the plant whatsoever. If you would like your young plants to grow faster this is a good way to make that happen.
What color of light is best for Seedlings?
When seedlings first come out of the soil they are in a vegetative stage of growth. This means that blue lighting will work best for seedlings. These are lighting spectrums of between 480 nm to about 520 nm for the blue light spectrum.
Can LED lighting burn by Seedlings?
Yes, if you have your LED lights close to your seedlings they are still hot, not as hot as a HID light. They are still hot enough to burn your young plants. Growers can use the hand test, to check if the light is too hot or too close to your seedlings. Take the back of your hand and place it under the lighting. If your hand gets warm then the light is most likely too close to your seedlings and you will have to move it up some. Remember the plant is under these lights for at least 16 hours a day and if the light is warming your hand, it will also be warming the young cannabis plants as well.
Best Lighting for Cannabis Seeds Conclusion
There are many best lighting for regular cannabis seeds however we recommend using LED lighting with dimmers so you can adjust the light for the best lighting output while also balancing the energy needed for the seedling stage of cannabis growth. LED lighting for seedlings is cost efficient and provides the best lighting spectrum for young cannabis plants.
Before you start planting check if you cannabis seeds sink or float!
