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seed starting with LEDs  RSS feed

Erin Beth
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Hi, I'm new here.  I hope I'm posting this question in the best location.
I live in the far north of VT, I've had some success with starting my seedlings on my windowsill but I'd really like to get them a more robust and healthy start.  My usual windowsill has a 12" wide ledge and fits two standard garden flats side by side; my idea is to build a shelf that will fit there so I can have two tiers of flats (4 total).  I decided to take a chance on ordering these lights:
I'm not having a lot of luck finding information about using these, I think most people use them for growing marijuana so a lot of what is written is not applicable to me (trying to grow in enclosed spaces, trying to grow plants to maturity, etc).
So here are my questions:
1) I bought 2 3m sections, my shelf is going to be approximately 12" deep by 45" wide.  I figure I will snake them back and forth, and not connect them in any way but plug them in separately.  Will this be enough light?  Too much?
2) I saw somewhere that someone attached these to an aluminum bar to dissipate the heat.  I thought one of the advantages of LED is that the don't generate much heat?  Do I really need to do this?
3) Any other thoughts or warnings for me?

Thanks in advance!
Bryant RedHawk
garden master
Posts: 2712
Location: Vilonia, Arkansas - Zone 7B/8A stoney, sandy loam soil pH 6.5
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Those lights are designed for growing plants so they will work fine.
having each strip so you can turn them off and on independently is a really good idea, you can vary the intensity of light, just like normal sun travel across the sky does.
LED's do produce heat, and a lot of it, so a heat sink is a good idea.

Is it possible to have to much light?
Yes, plants can get too much light.

Light that is overly intense can cause leaf burn, reduce the efficiency of chlorophyll and cause wilt through excessive respiration.
Also, plants need dark time, that is when they take in CO2 and give off O2, think of you, you need dark time to heal and rest, yes?
Plants are no different in that respect.

Andrew Brock
Posts: 42
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Those will certainly work but for what stages depends on the power per led. Very little power would be needed to start seeds. A good led growlight drives each led at about 1.5watts so for starting 2 flats less than 30 led would be needed, probably much less (assuming 1.5w/led). Leaving them not serially connected is good because you can dial in the amount. Led do generate heat but again it's dependent on power rating. All led growlight a I've seen have a heat sink that is as large as he housing permits.
It's exactly the same and completely different as this tiny ad:
The Earth Sheltered Solar Greenhouse Book by Mike Oehler - digital download
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