Sunlight vs HPS

[Tom OBrien]

I finally broke down and bought a real HPS grow light after growing a big batch of really long stringy pea plants that produced no pea pods. And while it is a very big improvement over the T-8 grow lights with year old bulbs I had been using, I can't help noticing that my outdoor peas are now kicking ass on my indoor plants even though they were started later. Of course, the indoor garden does have a pretty big edge in this area from October through March, but when it warms up it looks like sunlight is hard to beat.   

[Richard Winkel]

HPS doesn't produce a balanced spectrum.  You need 3 bands if I recall: blue, red and deep red.  The HPS is lacking blue.  Try reinstalling the fluorescent to go with the HPS.

[Tom OBrien]

The T-8s actually weren't terrible for lettuce and produced a few peas when they were new. But I wouldn't go with those again. I was thinking of trying a CMH bulb next.

[Carey Ma]

True! Sunlight can't be beat! Thats what nature intended and developed. T-5s are only good for starting plants and growing sprouts. T-8s are parctically useless IMO. You wold do well to use 1,000 watt HPS or MH for indoor plants. Over the past two decades, I have grown all sorts of plants indoors with HID lights of every sort and can vouch that it is possible...However, at a cost. Cost in eletricity to overcompensate for the limited (spikes) of spectrun and PAR (photoactive radiation) plants need to be healthy.