Questions on CFL light distance and humidity for seedlings

VapeItNow

Member
Hi guys,

My five seedlings are on their 2nd day of growth. My light for now is a CFL 125W Fluorowing Grow Light. The instructions say, "Keep the light approximately 6 to 12 inches off the tops of seedlings and/or vegetation. The closer the light source is to the garden, the higher the intensity, but narrower the coverage."

I have the bottom of the bulb 6" from the top of the seedlings. It seems to me that I could have it closer. Here's some pics of my setup.

DSC_0032.jpgDay 2.jpg

The image on the left shows the bottom of the bulb at 6" above the rockwool before the seedlings came up. Today it is now 6" above the seedlings. The temp 3" below the bulb is 79 degrees. There is mylar on the side and back, and a white reflector board leaning on the right to enclose the small area. The fan keeps the light cooled and the area temp around 72. I have a probe in one of the rockwell cubes that's connected to a thermostatic controlled heating mat, which is at about 77.6 degrees right now.

The image on the right was taken today, day two for the seedlings. Most plants have their 2nd set of leaves.

So, shouldn't I move the light closer?

My humidity is low, around 16%. I tried putting a little water in the tray and/or some damp wash cloths. That raised the humidity level just right, but then the temps fell into the low 70s and the heat mat couldn't keep it warm enough. Any suggestions?

Hope I explained it well. Thanks.
 

Ledhed

Well-Known Member
The light could/should be a bit closer. As far as temps, anything over 68 or so should be fine for now, as long as you don't let it get much over 80ish.
 

Sunbiz1

Well-Known Member
Why does April look unhappy?.

78 is the ideal temp for new seedlings and cuttings, you're going to need at least 3 times the amount of wattage in a few weeks for that amount of plants. I use 600 CFL watts spread out over 14 bulbs at varying heights for 4.

Good luck!
 

VapeItNow

Member
April has the seed casing still attached to the leaves, and some of the rockwool is poking up from where she sprouted. I pressed that back down. Should I remove the seed casing? I lowered the light to 3" above the seedling's tops and removed the seedling tray cover. The temp above them now is about 75 degrees. Since I am in NM and it's very dry here, I will probably need a vaporizer. I'd better order my tent (4x4) now so it'll be ready in a few weeks. I'm getting a Hortilux Super HPS EN Lamp - 600W for that, plus a MH 600W bulb for flowering.
 
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