what type of led lights for growing weed

What type of led lights for growing weed

The most important thing to learn about your new LED grow light is the proper distance to keep it from your growing cannabis plants. The recommended distance varies greatly from LED model to model, but getting it right will make a huge positive difference in your results! So many growers unintentionally hurt their plants by keeping their LED grow light too close.

With LEDs, always look at the “actual power draw” or “actual power consumption” which is the amount of electricity the LED panel actually pulls from the wall. When comparing different LED grow lights, this is the closest you get to a side-by-side comparison.

How Far to Keep from Plants: 36” away in vegetative stage, 18″ away in flowering

Unlike CFLs, LEDs don’t need to be adjusted almost daily

Kind LED Grow Lights

How Far to Keep from Plants: 32″ is the recommended starting distance from the plants.

How Far to Keep from Plants: The manufacturers of this Kind LED grow light recommend that the lamp be kept at least 36″ from the tops of your plants for the best results. This model is very, very powerful and keeping it too close will give your plants light burn!

Grow Space: 2.5’x3.5’’

Advanced Platinum LED Grow Lights

Kind LED panels have recently been becoming very popular on the cannabis growing scene and seem to be getting great results especially when it comes to yields. However, they are definitely pricey even for LEDs, so that is a big consideration!

You are willing to do some research to determine the best LED grow light for your space (this article will help guide you)

What type of led lights for growing weed

When comparing both technologies, always compare light levels of the entire grow and not just fixture to fixture. I cannot stress enough that there is no such thing as a 1-for-1 replacement of HPS by LED! That simply does not exist in the marketplace. Yes, there are LED fixtures that exist when measured directly beneath the fixture. The output looks equal to or even greater than an HPS. But, when you move the PAR sensor any direction from centered beneath the LED the light level decreases much more under the LED than any HPS fixture!

This is a big consideration to consider when comparing these technologies. There is no easy math to calculate an ROI for this but when comparing light plans from one source of light to another be sure to take into consideration the distance of the light source from the canopy.

As a plant that does not have sufficient lighting in veg will not produce as well in flower. That said, the spectrum with the most blue did produce the flower with the most terpenes and THC.

Efficiencies

Another area you should always do your own math on is the BTU calculation for your grow room. Yes, LEDs produce less heat than HPS and this can be the deciding factor. As the cost to cool your grow room can be one of your highest production costs. Your AC load is based on the amount of BTUs produced from your fixtures. This is simple math as 1 watt equals 3.412 BTUs. No matter what 1000w HPS fixture you use the BTUs from that fixture will be 3412!

ALWAYS ask for a light plan that shows an average light level in micromoles AND a uniformity average (hopefully above 90% uniformity). Most LEDs are a very directional source of lighting. If a crop is grown under lighting that is not uniform across your canopy but instead has “hot spots” and “dark spots” it will cause you trouble as the hot spots will use more water, evaporate water, absorb nutrients, etc. at a different rate of speed then the dark spots! To truly have an “apples to apples” comparison be sure to compare light plans with the same targeted light level in micromoles and close to the same average uniformity number. If a supplier cannot provide you with these numbers then it may not be someone you should be considering.

Heating/Cooling

After veg and moving to flower, most growers also agree that switching to a light source with more of the red spectrum is better for flowering. The old standard has been to use either CMH or fluorescents in veg and switch to HPS into flower. This is the tried and true lighting recipe for indoor cannabis growers. By far the majority of cannabis produced in North America today is grown in this way. With the onslaught of LED lighting manufacturers jumping into this new “green rush” of opportunities we are seeing this standard lighting recipe being challenged more and more.

What about growing in a greenhouse? From our graph above showing the spectrum of sunlight compared to that used for photosynthesis is there any benefit for using a light source where you can dial in the spectrum to add more blue? The natural light received by your crop in a greenhouse will cover all of your light spectrum needs. So the big question for greenhouse grows should center more around the ROI comparisons between LED and HPS — not about light spectrum needs. This is not something you will hear from light manufacturers of LED lighting. Your LED-only supplier will have you believe you NEED their spectrum specifically!