The driving factor in determining the best LED grow light depends on the area you need to cover. Customer’s always ask what light they need or which one we recommend, but without more information it is difficult to direct them. Therefore, knowing their ‘coverage area’ helps guide the rest of the LED grow light decision process.
It might be safe to assume that most home growers setup a grow in a 100 x 100 cm or 120 x 120 cm (3,3'x3,3' or 4’x4’) area. But some people grow in a 60 x 60 cm (2’x’2), 90 x 90 cm (3’x3’), 150 x 150 cm (5’x5’), or a rectangular area. Some home and commercial grows are quite large and require several fixtures. Knowing the exact space you want to grow in helps narrow down how small or large of a light fixture you need. Too much light is wasted money, but not enough light can lead to less than desirable growth and yields.
One of the specifications on an LED grow light is the ‘recommended coverage area’. We highly suggest that this is the first thing you consider when choosing a fixture. The ‘recommended coverage area’ specification should primarily be used for smaller grows that only need one or a few fixtures. But larger commercial grows that require several fixtures could require fewer fixtures due to the effect of light contribution from nearby fixtures. Commercial applications should always consult and obtain professional advice and often a light plan before installing lighting. A light plan shows how many fixtures are needed to obtain the light level targets in a given coverage area.
Figure 1: Optilux PPFD Measurement
Figure 2: SolarSystem 550 PAR Measurements at 18'', 24'' and 36''