420 Magazine Background

Seedlings and light

I was wondering which would be a better scenerio.

Got 12 seedlings. They are starting to stretch. They were started on a 600watt halogen(i know its bad, was waiting for my HPS to come in).

Now which would be better for the seedlings

4, 40 watt flourescent a few inches away from them

or the 600 watt HPS as close as i can get it without getting to hot?

I heard flourescent was good for seedlings. Any truth to that? what would you do?

if I should use the flourescent now, when should i introduce the 600watt HPS?


Well-Known Member
Use the CFL's for now, until the plants are mature enough to flower. Then switch to the 600w HPS when you begin to flower with a 12/12 light/dark cycle. Do not use halogens as they create alot of heat and do not provide the necessary blue spectrum of light for vigorous healthy vegetative growth.
Ok....so i can use the CFL's, but from what ive heard, wouldnt the HPS give better light than the CFL's? and what would be the problem if i put the 600watt HPS on them now instead of waiting for flowering?


Well-Known Member
HPS lighting puts out a very red-orange spectrum of light, which is poor for photosynthesis. During veg growth, the plants will stretch much more using the HPS then if you used the CFLs. Some companies offer HPS bulbs that produce more light in the blue spectrum (more suitable for veg.) than a conventional HPS bulb and conversion bulbs (HPS-MH) are also an option.

Veg. time is only 3-6 weeks for most strains, if your doing it on the cheap, stick the CFLs about 3-4 inches from the tops of the plant consistently through the veg stage and then add the 400w HPS when you are ready to flower. Also, CFL run cooler allowing less risk of damage to young plants and seedlings and they also cost less to operate. If you have money to spare, buy an MH system for veg. instead.
Top Bottom