zxcvbob wrote:

John Hines wrote:
Mark Anderson wrote:


In article says...

That's true. I have a florescent setup for vegetative growth plants
using regular ballasts and 40W bulbs from Home Depot. I'd go with Metal
Halide but I heard they can be a PITA to maintain.

No problem at all. You have to change the bulb once a year or so. And
you can get bulbs from HD, since they are used as warehouse lights and
such.

I read that the MH bulb's color spectrum shifts fairly quickly which you
can't see with your naked eye. I debated with myself between HPS and MH
but chose HPS for stability.


The plants in my living room are growing just fine under a 250W MH lamp.

You can spend more $$ and get a MH with a different spectrum, even up to
5000K or so. They are commonly used by reef aquarist, who are much more
concerned about spectra.

But yes, changing the bulbs on a routine schedule, like yearly, is
better than waiting for them to burn out.


But the HPS is a red spectrum flowering
light so some plants didn't do so well under it last winter. However,
it might be worthwhile to get one of each and run the MH light from
November to January or February and then the HPS light from January to
planting outside time. I'm still learning about it.


There are advanced tech bulbs, like
http://www.altgarden.com/site/bulbs/page1hps.html designed for better
spectrum, and better growing.


I'd like to try "Deluxe" HPS lamps. They have a pretty good color
rendering index, so they might provide enough blue light for the plants
to grow better. I've only seen Deluxe HPS lamps in the lamp
manufacturer's catalogs, never seen them for sale.

Alternative garden, the link above has both MH and HPS spectrum enhanced
bulbs. The only other place I've seen interest in these kind of bulbs
is for aquariums, who need 5000K and above for coral reefs.

Everyone else is interested in the most light for the least $$, so the
color quality is not important. The specialty bulbs are more expensive.