EDITOR’S NOTE: Since this article was published four year ago, one company has stepped up to make LED grow lights that equal or surpass HID (high intensity discharge) grow lights.
Please see this article for more information.
The industry standard for indoor marijuana lighting has been high intensity discharge (HID) lights.
But when marijuana growers use HID bulbs, they get a lot of heat that can be detected by rippers and police using infrared radar.
They get increased cost for air conditioning and venting, and the potential to burn the hell out of yourself on bulbs that can leave scars on you.
That’s why marijuana growers use non-HID lighting such as fluorescent, induction, plasma, and LEDs.
LED manufacturers claim LEDs generate a better light spectrum for marijuana, with lower electricity cost, and less heat.
If LED grow light manufacturers and advocates were totally honest with us, they’d say only the following:
- LED grow lights of adequate wattage, with high-watt, multi-colored chipsets, and top quality construction and design can grow sticky buds by themselves without other lighting, in small closet gardens, chamber/tent gardens.
- LED grow lights can be used as stand-alone marijuana lighting for clones, seedlings and throughout grow phase.
- LED grow lights by themselves are adequate in bloom phase for marijuana plants under five feet tall, grown in small chambers, SCROG, Sea of Green, and similar situations.
- Marijuana growers have repeatedly been scammed by LED manufacturers and sellers.
- Almost every marijuana grower who tries LED grow lights has some horror story about the LED equipment failing, hard to get service or refunds, LED manufacturer out of business, etc.
- If you’re measuring success by how many grams of marijuana are produced per watt of hydroponics lighting electricity you pay for, some very expensive LED units can compare favorably with HID.
The most successful indoor commercial marijuana grower I network with is using 1000-watt HIDs as his main lighting, and augmenting those with high-end LED panels.
He also tried to augment his HID rooms with T-5 high output fluorescent bulbs, but says the LED units he bought were smaller, easier to hang, and had a tuned light spectrum more likely to spur photosynthesis.
Sometimes he uses the LED panels as vertical lighting. Other times as top lighting.
His main goal is to take advantage of LED panels whose manufacturers claim that their diodes generate UV (which allegedly makes more cannabinoids) and other beneficial light spectrums.
He also uses LED panels to combat light shadows and to provide side lighting and penetration for long buds when he’s growing Sativa-dominant strains, or when plants are trimmed, ScROG, or otherwise super-dense.
“I bought three different brands of LED grow lights for my marijuana grow op,” he reports. “The cheapest was $900. The most expensive was $1900. I’ve had diodes fail on two of them after only a few hundred hours. One unit didn’t work at all when I got it home from the store. But I think they’re worth it. However if I wasn’t using HID lights as my main source, they wouldn’t cut it.”
Here are some insider tips for marijuana growers buying and using LEDs:
- LED grow lights work best with autoflowering, Sea of Green, SCROG, chamber/tent grow ops with marijuana plants less than four feet tall.
- Don’t buy LED units from a manufacturer that’s been in business less than three years.
- Contact the manufacturer directly (don’t just believe what the hydroponics retailer tells you) and get in writing their warranty and return terms.
- Ask LED grow lights manufacturers for a guaranteed analysis of their PAR light spectrum, whether they’ve tested their PAR spectrums on marijuana, and what the tests showed about yield weight and THC percentages.
- Never buy an LED unit unless you’re sure that if it fails in any way within the first years that you get a replacement unit absolutely free of charge, in a timely manner, and with free repair and return shipping.
- Only use LED grow lights that have at least 5-watt chipsets. If possible, get units with 10-watt chipsets.
- Experiment with how close you keep your LED grow lights to your marijuana tops.
- Start with a smaller, less-expensive LED unit and test it before you buy a larger more-expensive unit.
- Look for LED grow lights that have professional heat sinks, fans, depth, instructions, and safety features.
IMPORTANT UPDATE: Long after this article was published, an American company called Lush Lighting stepped up to create LED grow lights specifically designed to boost growth rate, plant health, potency, and harvest size.
Read here to find out about the only LED grow lights actually designed for cannabis.