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Aya
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Plant Lights Burning Seedlings...Help?

Hello All,

I purchased a light that was marketed as being specifically for plants, hoping it would help my seedlings thrive before transplanting them outside this year. (IE: Tomatoes, Cucumbers, & Peppers). However, I've found that the lightbulb gets extremely hot, to the point where I can barely touch it without burning myself. I thought plant lights didn't emit heat? When I place it near my seedlings, they burn. And when I move it further away, my seedlings become leggy and fragile. Any tips? I'd like to have some thriving plants this year..

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hendi_alex
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Get fluorescent lights and they can be moved to within a couple inches or closer to the foliage. Some plant lights get very hot, but those usually put out so much light that they can be placed much further away from the plants. I'm not sure what you have, but since the plants are already growing, I would very quickly get adequate fluorescent lighting before the plants get far too leggy or get damaged from the heat of the existing light.

lexusnexus
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Was going to make the same suggestion for distance above plants. It is a T5 light? They are highly recommended over on the orchid forums.

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rainbowgardener
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What you need is ordinary fluorescent tubes in ordinary shop light fixtures.

But what specifically do you have? One problem that people have written in about a couple times, [that I cannot find in search for anything] is that certain kinds of bulbs, even compact fluorescents, in reflector hoods are designed to be used in the bulb up/ base down position or horizontal. Used in the bulb down / base up position, the heat rises into the reflector where the base is and collects there and then every thing gets very hot. It's very hard on the electronics then and the bulbs burn out way too fast.

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Aya
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This is currently what I'm using:
https://www.homedepot.com/p/Philips-75-W ... /202766841
When I was in HD I had grabbed regular florescent lighting with a ballast, then asked a worker to make sure it was what I needed and he told me to grab this instead. I probably would have been okay with my original pick...
Also, is there a way to save leggy seedlings or should I just start from scratch? Is it too late to re-start my tomatoes, cucumbers and peppers? We have a pretty short growing season for hot weather veggies like these. I'm just north of Seattle..roughly zone 8A

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hendi_alex
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I only have to note one thing to see your problem. The light says 75 watts. That means that the light is incandescent and is more of a heater than a light source. Buy a compact fluorescent in warm white (23 watt) and you will be pleased with the result. A singe bulb will give adequate light for about one square foot of area. I use mine in a $6 clip on reflector lamp from Lowes. They are located with the extension cords

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applestar
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Aya wrote:Also, is there a way to save leggy seedlings or should I just start from scratch? Is it too late to re-start my tomatoes, cucumbers and peppers? We have a pretty short growing season for hot weather veggies like these. I'm just north of Seattle..roughly zone 8A
See if this looks like what you are dealing with...
:arrow: https://www.helpfulgardener.com/forum/vi ... 15#p326115
...the story continues to the next page of the thread...

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Aya
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Thanks for the tips everyone, hopefully I'll be able to save everyone!

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rainbowgardener
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hendi is right. It's an incandescent. Despite the bum advice you were given at the store and the fact that the thing is apparently sold as a "plant light" you can't grow plants under incandescent lights. As you have already seen, they give off too much heat. If it is close enough to do any good, it burns the plants. If it is far enough away, they get leggy. You would have been fine with the fluorescent tube you picked originally.

According to this map: https://www.plantmaps.com/interactive-wa ... te-map.php , your first frost date in fall isn't until Nov, which sounds like a very long growing season (as would be expected in zone 8). But maybe you weren't talking about freezing, just about cool and damp and not enough sun?

Cucumbers I would re-start. They are quick to germinate and quick to grow and they can't go in the ground until the soil is well warmed, so you have time to start over with cucumber seeds.

The tomato seedlings, if they are just leggy should be fine. Pinch off the seed leaves and re-pot the plants buried up to just below the first true leaves. They will root all along the buried stem and do well.

The peppers, you may just want to buy started plants this year. They are the slowest to germinate, slowest to grow and produce. They don't respond very well to the bury the stems trick. I plant pepper seeds the beginning of Feb and may not harvest my first peppers until July.

Sorry you got duped like that! :shock:

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Aya
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Rainbow,

Thanks for the advice. I'll restart the cucumbers, my tomatoes don't appear to have any true leaves yet - just the two little seedling leaves so far. The pepper seedlings are still really tiny, they only just germinated..so maybe there's hope for them as well.

And as far as the growing season, I was indeed talking about lack of sun. Last year we did really well, but as a general rule, the sun doesn't stick around long enough for my plants to produce anything. It seems to be kind of hit or miss. We'll see how this year goes!

That being said, we get lots of production from cold weather crops (Broccoli, Beans, Peas and Salad Greens), I just hope we get enough sun/warmth for the tomatoes and cucumbers. I'll be sure to try the buried technique on the tomatoes. Do I just leave the seedling leaves on then? If I pinch those off, it'll just be the stalk with no leaves..

Thanks Again!

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applestar
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Yep. Rainbow was talking about tomato seedlings that are farther along with several sets of true leaves. With spindly babies with seed leaves, bury to about 1/4" below the seed leaves and put in good light. Mine were placed 1" below 65000K T-12 (older fat fluorescent light tube) lights. CFL bulb, T8 should be 2" away and T5 can be 3" away because they are hotter but brighter (not brighter in case of CFL bulb actually)

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Aya
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Thanks Everyone,

I'll try these techniques, and hopefully will have a good harvest this summer :lol:

GEOSAN
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Aya, could you help us to help you in the future by changing your location field in your profile to "Seattle 7b.
Not everyone knows where in the world the "Emerald City" is. We may know about gardening but we also may be geography challenged. :-) You are in Seattle aren't you ?



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