ALTHOUGH ULTRAVIOLET PHOTONS
don ’ t contribute much to photosynthesis , they do cause some interesting responses for resin and anthocyanin production .”
The green / yellow-heavy ratio supplied by HPS lamps is one reason that technology has always been known for good penetration . Human eyesight is most sensitive to light at a wavelength of 555nm , so green light is important for visual purposes as well . Anyone who has worked under purple lights knows how difficult it can be to diagnose potential problems .
BLUE ( 400-500nm ) — Conversely to far-red light , blue light slows cell division and expansion . While that might seem like a bad thing , this effect helps produce sturdy , compact plants , and it ’ s the reason many growers love MH lamps for vegetative growth . Plants grown without any blue photons tend to exhibit weak , stretchy growth . One possible concern with blue light is its effect on the human circadian rhythm . Some studies have shown disruption of sleep cycles in subjects who were exposed to high levels of blue light . Growers who work in their gardens late at night should take this into consideration .
ULTRAVIOLET ( 10-400nm ) — While infrared light is what makes sunlight feel warm on your skin , it ’ s the highenergy photons in the ultraviolet ( UV ) range that damage skin cells , causing sunburn . Although ultraviolet photons don ’ t contribute much to photosynthesis , they do cause some interesting responses for resin and anthocyanin production . Many of these effects vary wildly from species to species and even cultivar to cultivar . Ultraviolet light also plays a role in pest and disease control .
The Perfect Plant Spectrum DOESN ’ T EXIST
If the quest for the perfect plant spectrum has taught us anything , it should be that there is no such thing . Each color range should be used as a tool to steer plant growth and development , but the effects on workers should also be taken into account . Today ’ s high-performance plant genetics were bred for decades under sunlight and HPS lamps , and experienced growers know how to get high yields in those conditions .
With all this said , grow light manufacturers should listen to the needs of growers and avoid trying to reinvent the wheel with a Holy Grail spectrum .
64 Maximum Yield