As regards specific types of LED grow lighting systems, there are numerous configurations with choices between UFO grow lights (so named because, well, they look like UFOs), grow light panels and single spot lamps. Then there is the color balance to consider. Typically the ratio varies between 4:1 and 8:1 red:blue and these days the balance can also be varied. When reviewing the red to blue light balance, be sure that specific wavelengths are stated (somewhere in the region of 660nm for red and 460nm for blue). Just “appearing” to be red or blue is not good enough.
Many 1st generation LED grow lamps were bi-band (just red and blue) which experience has shown to be insufficient for most plants. Although these two wavelengths satisfy the bulk of a plant’s needs, most still require trace amounts of light from other portions of the spectrum. More modern (so-called 2nd generation) system are tri-band and incorporate an orange component and there are now 5 band lights that match both chlorophyll absorption peaks in the red and blue zones plus orange. A good example is the Illuminator Series of LED Grow Lights, the supplier of which also provides an excellent example of what characteristics to look for when sourcing grow lights.
Finally, the lighting system you choose should be guided by the type of plants you aim to grow (are they tall, bushy, especially leafy, etc) and the physical space. For example, is it a greenhouse or completely indoors, what are the clearances, is it for a grow tent? One aspect of LED grow lights in particular, namely the fact that they run cool means that instead of providing ventilation and ducting to dissipate excess heat, you may need to consider instead providing additional heating. Not only do LEDs give off very little heat anyway, but many systems have built-in ventilation fans which further cool things down. Many of the larger grow tents for example provide for a powered ventilation system to cope with the heat from an HID lamp. Obviously this is going to be way too much for indoor growing using LED grow lamps.
LED grow lights – the final verdict
So is the buzz about LED grow lights all hype or are they for real? Well, don’t trust to “professional” grow light reviews (which not infrequently are written or commissioned by a supplier as a marketing tool) – simply check out what regular folk who just want to grow plants indoors have to say about their own real life purchases and experiences courtesy of the entirely open Amazon reviews. Sure, there’s the occasional professional curmudgeon for a reviewer and the odd rotten product, but by and large LED grow lights completely live up to the claims, especially in the demanding domestic consumer market. And knowing what plants need and how LED lights work, now you know why.
Still not convinced? Have you ever considered gardening in space? Well, probably not, but NASA have since it’s the only possible way to feed the crew on a trip to Mars. This is a seriously demanding environment with zero usable natural light available plus massive constraints on weight, spare parts, heat loss and power consumption. LED grow lights tick the boxes on every score and especially because of the ability to target only the spectral wavelengths required and save further energy by avoiding producing unusable light. And the results? Apparently the scientists ate the results and pronounced them delicious!
Finally, keep in mind that at the end of the day, what counts most with grow lighting is both light intensity (not to be confused with brightness) and accurate spectral calibration. One without the other is of little use and this simple fact underpins why LED technology is the way forward for horticulture lighting.