What to look for when selecting LED grow lights

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Selecting an LED grow light can be a daunting exercise, considering the number of options and the fact that manufacturers do not market their specifications in a uniform way (this should be changing soon with the horticulture lighting label program). We put together this simple guide to arm our customers with the hard questions next time they encounter someone marketing "The Most Advanced Grow Light". 


Any reputable LED grow light manufacturer should be able to provide a third party certified test result indicating the efficiency in photonic units (PPF, in micromoles per watt or μmol/W). In our experience, even well established LED lighting manufacturers have been using false numbers as recently as Summer 2018. We expect this behavior will come to an end when the horticulture lighting label is finalized. 


Any LED grow light manufacturer claiming to have an optimal spectrum is misleading its customers. This is because plants will respond to many spectrums quite well, while no one spectrum is perfectly suited to all stages of plant growth and all cultivars. GrowFlux products are capable of millions of broad and narrow spectrum profiles without sacrificing output, allowing cultivators to develop tailored spectrums for their unique conditions, cultivars, and desired outcomes. 

Power Factor

Any modern LED lighting fixture should have a power factor of at least 0.90, which will be required by the Design Lights Consortium as they release their final policy. All GrowFlux products feature active power factor correction typically exceeding 0.95. 

Ingress Protection

Any quality horticulture lighting product should be listed for wet locations, otherwise fixtures will not stand up to greenhouse conditions or sanitizing agents used indoors. GrowFlux lighting products are Listed for Wet Locations, and are able to withstand a high power jet of water from any direction. 


Active cooled fixtures are able to operate at cooler temperatures and across a wider operating temperature range compared to passively cooled fixtures. If you are considering a passively cooled fixture, look closely at the operating temperature range and ask the manufacturer whether the fixture will perform in stagnant air conditions, which can easily occur (especially when mounted to a rack). Finally, high operating temperatures limits LED life, so be sure to ask for the expected 90% or 70% lifetime for a passively cooled fixture. All GrowFlux products are guaranteed for 90% output at 50,000 hours. 

If you are considering a fan cooled lighting product, ask the manufacturer the Mean Time Before Failure (MTBF) for the fans, and what happens in the event of a fan failure. GrowFlux uses waterproof IP68 fans with an MTBF of 100,000 hours. In the event of a fan failure, fans are user replaceable in minutes and are covered by our 5 year Limited Warranty. 

PAR maintenance

Even today's worst performing LED grow lights should be able to hit 70% output at 50,000 hours. GrowFlux products are guaranteed for 90% output at 50,000 hours. If your manufacturer can't provide their TM-21 Energy Star calculations, stay far away. 

Optical distribution

PAR uniformity on the canopy is nearly as important as energy efficiency. Look for PAR maps which indicate the mounting height and PAR levels over an area representative of your intended application. GrowFlux offers PAR maps which show the expected PAR levels for a variety of cultivation situations and mounting heights. 


Tunable fixtures offer the ability to tailor the light spectrum to the stage of growth or specific outcomes. If you are looking at tunable fixtures, be sure to understand how tuning the spectrum affects the output of the fixture. Most tunable LED fixtures only emit one spectrum setting at full power; any modified spectrum from the full power setting reduces overall PAR output of the fixture. GrowFlux offers the industry's only LED fixtures with an extended tunable range, allowing cultivators to deliver millions of spectrum settings at full output. 

Certifications & Labeling

In North America, LED horticultural lighting products should be certified to UL1598, a safety standard for commercial lighting products. Products that do not comply with UL1598 are not eligible for energy rebates or Design Lights Consortium approval. 

In the near future, an industry standard Horticulture Lighting Label will be formalized. This lighting label will require third party lab reported total PPF as measured by an integrating sphere as well as a PAR map showing PPFD. Once this standard is released, do not consider purchasing an LED product which does not comply with the label - manufacturers who do not comply with the labeling requirements likely have performance issues to hide. Follow our blog for updates on the Horticulture Lighting Label. 

Wireless & control

If you are considering a lighting solution with control capability, make sure you consider how much time and expense is involved in networking fixtures. We have encountered wireless grow lights that take several minutes to an hour to configure - for each fixture. We have also encountered connected lights which require data cables and additional external controllers which add to the cost and installation time of the solution. Finally, be sure to find out if the control solution requires a separate license fee or setup charge. 

GrowFlux products are networked by our own high reliability AetherMesh wireless technology, capable of networking sensors and fixtures 500+ feet through multiple walls indoors. Our control software is included for no additional cost. Check out our other blog posts on how our wireless technology saves time, money, and headaches