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TomatoGirl
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Location: Ontario, Canada

LED grow light for seedlings

This year as I bought some LED grow lights and I am noticing my seedlings look much different.
Much darker and I’ve noticed some curling of a few of the cotyldons leaves.
I bought the light from Root Farm.
Anyone else have this experience?
Not sure if it’s a good thing or not..
They are currently getting about 10-12 hours under the lights.
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pepperhead212
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Re: LED grow light for seedlings

What type of LED lights are those? I have 5,000k flourescents, with about 3,224 lumens, and this year, I got some LEDs from Harbor Freight - 4 foot 5,000k, with 5,000 lumens, and I grew some tomato seedlings under 2 of them - a little less than the 4 fluorescent bulbs I use over 2 trays, but the tomatoes did well, without getting at all leggy, and the leaves were somewhat darker, with none of the purple undersides I often get, but I they don't get leggy under the flourescents, either. I don't think that you have to worry about those curly cotyldons - I notice that on some, and I just figured it's a thing with that variety. The seedlings look fine, to me, except that they seem to be reaching for the light

10-12 hours seems low for growing seedlings - some run them 24 hours, I do 16 hours.
Dave

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TomatoGirl
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Location: Ontario, Canada

Re: LED grow light for seedlings

All the info I have says it’s 45w broad spectrum with red, blue and white lights. Underside of the leaves are looking purple though.
I’d have the lights on longer, only right now they are in my kids bedroom as it’s the only place for it right now and I can’t have it on while he’s in bed.

pepperhead212 wrote:What type of LED lights are those? I have 5,000k flourescents, with about 3,224 lumens, and this year, I got some LEDs from Harbor Freight - 4 foot 5,000k, with 5,000 lumens, and I grew some tomato seedlings under 2 of them - a little less than the 4 fluorescent bulbs I use over 2 trays, but the tomatoes did well, without getting at all leggy, and the leaves were somewhat darker, with none of the purple undersides I often get, but I they don't get leggy under the flourescents, either. I don't think that you have to worry about those curly cotyldons - I notice that on some, and I just figured it's a thing with that variety. The seedlings look fine, to me, except that they seem to be reaching for the light

10-12 hours seems low for growing seedlings - some run them 24 hours, I do 16 hours.

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TomatoNut95
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Re: LED grow light for seedlings

What type of tomatoes are you growing? I have grown many tomatoes from seed and have seen the purple tint on leaves and stem. That can depend on the variety. Dark fruited types can show that. My Blue Beauty will. And I don't think it's nessesary you leave your grow lights on 24hrs a day. Seedlings may need periods of darkness.

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rainbowgardener
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Re: LED grow light for seedlings

Purple undersides of tomato leaves is usually an indication of not enough light. I also keep grow lights on 16 hrs a day. That helps make up for how much less intensity of light they are getting compared to sunshine. How close are the lights to the plants? They need to be just a couple inches above them.
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