How high to hang grow light?

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My cantaloupes just sprouted so I hung my grow light but I’m confused. The instructions say to hang it like 12” above for seedlings, but an article I was reading all about how to care for seedlings indoors says to hang as close as possible without touching the seedlings. Which should I do?
 
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It would really depend what kind of grow light I think. I use a mars hydro 600 to start my pepper and tomato plants and I find about 14 inches works best but I've heard others say 24 to 36 inches. I had it at that first year I used it and found they were stretching to the light. I would suggest following the instructions at 12 inches and if they stretch then lower it a bit. I wouldn't put it too close for seedlings.
 
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Depends on the type of light and how much power it puts out and the beams width.

My cheap Walmart LED shop light works good at 3" above the top of the plant but at around 2.25" the plants cant stand it and curl down and raise all kinds of fuss and they don't wont to recover if they sit at that height for too long. The light does something negative to them as they twist, curl, turn white and stunt. At 4" the seedlings want to get leggy so there is a very narrow range to work with my light.
 
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Thanks! Also, my seedlings got pretty leggy before using the light because I didn’t install it soon enough; they had 2-3 days from sprouting to when I installed. They’re still leggy but have definitely opened up and responded to the light; will they stop being leggy and tall at some point? Here is a pic after having 1 1/2 full days of grow light so far.
 

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Your going to have a hard time with them being that leggy. You might want to put them in a deeper pot so you can bury the stem. When the others sprout they are probably going to want to equalize lengths with the leggy ones if you have a weak light light me so you may have to set the freshly sprouted ones on something to get all of the tops about the same height.

Leaves point upward are looking for more light. Leaves flat are happy. Leaves point donward are trying to escape too might light.

What kind of grow light are you using?
How far away is it from the top of the seedling? 12" still?
 
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Ok. So putting them in a pot wouldn’t cause a problem with the roots being so deep?
All the cantaloupes have sprouted except one which I don’t know if it will. My watermelons are fixing to sprout, but I would think they wouldn’t get leggy because they’ll have light as soon as they sprout.

Thanks for the tips about the leaves!

This is the grow light I have.

I think it’s actually more like 8-10” from the plant tops (it’s more like 14-16” from my basil sprouts, and they’re not getting leggy).
 
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Just to mention also you should have a fan on them, helps dry the soil so they don't get root rot. Also helps make the stems stiff, although I don't know if that part matters so much with melons as it does with tomato plants and stuff like that. I keep a fan blowing during the time the light is on circulating the air.
 
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Leaves point upward are looking for more light. Leaves flat are happy. Leaves point donward are trying to escape too might light.
That is very interesting. It makes total sense but not something I knew or thought about. Thank you for sharing that info. Some of my pepper plants furthest from the center of my light are pointing upwards. I have 2 lights going right now, one for tomatoes and one for peppers.. I'm going to have to figure something out. I went a bit overboard this year with them lol.
 
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This is the grow light I have.

I think it’s actually more like 8-10” from the plant tops (it’s more like 14-16” from my basil sprouts, and they’re not getting leggy).
You'll just have to experiment where to hang the light. I've been fiddling with my light ever since early Winter just so I wouldn't mess up my Spring transplants. I've messed some up plants and others have been perfectly grown. I'm still working the bugs out of my setup.

Something else I'm kind of noticing is that when my tomatoes and peppers started to get true leaves, the plant doesn't want to get leggy as bad, or possibly at all, as if had just sprouted and the cotyledons searching for the right light at the right height. So you might be able to hang the light higher when the plants get true leaves. That is my hunch anyways.
 

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