For cannabis growers over the last few years, under-canopy (UC) lighting has been a leading topic. Growers have been claiming significant gains in yield, flower quality and reduced labor. But does it work and is it worth the investment? Little reliable data has been available.
At California Lightworks we have developed new UnderCanopy LED Series, especially for greenhouses and large scale commercial indoor grow operations. Our theory was that under-canopy lighting would be an even greater asset in greenhouses, where the low light levels are notoriously low in the winter. We set out to test this theory with one of our long-time customers, Harborside/Statehouse in Salinas, California. Harborside is one of the original licensed cultivators in the country and has a large greenhouse operation. They agreed to test this new under-canopy series to gather real world data.
While there are several companies offering UC lighting systems, Megadrive offers some powerful advantages versus the conventional integrated driver approach used by our competitors. MegaDrive features a remote power supply so there are no electronics or power drops in the grow space. All the power cables, connectors, and hanging hardware is included with the fixtures. This greatly reduces the installation cost, increases LED driver life and eliminates many of the problems of running LED fixtures under the canopy which is a very humid and dirty environment.
Up to 80 under canopy fixtures can be run by a single power drop and can be located up to 500 feet from the grow space. All the fixtures, connectors, and cables are rated IP67 and are simple to clean. They are supplied with an adjustable stand that has multiple heights to accommodate various size pot or grow media. The lights can be dimmed from 0 to 100% and feature an optimized spectrum for bloom.
So, we covered all the bases as far as fixture design, but do they work?
The test was conducted during the months of October and November at the Harborside Greenhouse #2. The cultivar was Oreo Cookies, and they arranged two separate test areas:
Both areas were operated on the exact same 12-hour schedule for 8 weeks total, The results were as follows:
The test results were dramatic, with an increase in total dried, trimmed flower of 29.84 percent vs. the control! And the percentage of A grade (premium) flowers increased by 11% versus the control – 11% more flower at three to four times higher prices!
We have conducted a similar test with another large-scale grower in Salinas with very similar results – roughly a 30% increase in trimmed flower yield. This has exceeded our initial expectations.
Not only did we see significant gains in overall yield and the percentage of “A” flowers, but there was also a significant reduction in labor. Most cannabis growers practice deleafing to increase light penetration deeper into the canopy. Carefully pruning away the lower leaves and flowers in a one-acre greenhouse canopy is extremely labor intensive and a lot of cultivators simply don’t have the manpower or just aren’t willing to apply it. But that leaves a lot of flowers in the lower half of the canopy that ends up being immature. UC lights turn that canopy into mature flowers. This is a major source of increased yield and labor reduction.
The payback analysis in a typical greenhouse is compelling. Here we are assuming a base pound price of $800.00/lb. and a base yield of 1.5 lbs. per 5’x 5’ canopy section. Adding two 120-watt MegaDrive UnderCanopy lights adds 240 watts. With a 30% increase in yield from the 1.5 lb. baseline, we get an increase of .45 lbs. At $ 800.00 per pound, an additional .45 pounds equals $ 360.00 extra per harvest That’s roughly $100.00 more than the lights cost. The lights in this test case will be paid for in one or two harvests!
Rebates available for LED lights vary all over the country, but in the California market, the two major utilities, Edison, and PG&E, are offering a rebate for the MegaDrive UnderCanopy lights in 2025 that will pay half the cost of the fixtures. The rebate is prescriptive, meaning it has a much simpler process than other types of rebates. It is $79.00 per fixture regardless of the fixture wattage. This means that the payback period is cut in half again! There will never be a better time to buy Megadrive UnderCanopy lights in California than today! Compared to any other under-canopy system, the installation is quick and dramatically less expensive.
We at California Lightworks pride ourselves in being a leader in innovation in the horticultural lighting space, and 2025 is shaping up to be full of new innovations, starting with the exciting Megadrive UnderCanopy LED system! The MegaDrive UnderCanopy LED is currently in stock and available today!
Contact us for information on which lights are right for your application as well as free complete computerized light plans and grow consulting.
California LightWorks
7949 Deering Ave
Canoga Park, CA 91304
(800) 575-3475, Inside USA
(747) 444-3380, Outside USA
