Moving from Fluorescents to Leds

[caddy45]

I read through the replies quickly so this may have been covered but i didn’t see anyone flat out state it, the seedlings still need hardened off. Not from a temperature standpoint but light. Even though your lights may be full spectrum grow lights they still aren’t as full spectrum as good old sunlight and the tender little seedlings get sunburned so bad they die.
My first year I went from standard shop lights to full spectrum grow lights, I had a 6 bulb fixture anywhere from 2-8” from the plants and I switched after I had plants out of the soil and anywhere from 2-6” tall. Well that killed every one of my plants. Ok lesson learned. I threw another flat of seeds together under the new lights and they grew beautifully and since I was behind my usual starting time I thought I was in the clear as far as temp goes and I put a few tomatoes in the ground once they got big enough and, well, they died too. Same deal, turned white and never grew. That year I had to buy all my plants. Ha. Lesson learned again.
So even if the temps are warm enough, I still harden mine off in a typical fashion. Haven’t had an issue since.

[slugworth]

hurt your eyes led lights- you can put the plants directly in the sun.
some led lights are even sold with a pair of sunglasses.
if you can look at the lights without pain I wouldn't put them outside rapidly.
I make a tent out of cheesecloth for the weaning process of my regular grow lights.

[pepperhead212]

Welcome to the forum, @caddy45!

Yes, it's mainly because of the light that I harden off my plants - just sticking them out on my deck in the morning, and at that time of the year, the sun moves to where it's not on the plants fairly quickly, so I don't have to worry about forgetting them out there! Just put them out earlier, and earlier.

[slugworth]

I forget to move the plants to and fro,so if I can just set and forget like Ronco used to say, it is ideal.
Temperature is never a factor,it is strictly avoiding sunscald that triggers the movements.

[JRinPA]

Typically my plants go from inside (LED shoplights the last two seasons, fluro before that) to a small greenhouse covered in AG19 shade cloth that sees direct sun only in the morning. Or a tunnel similarly covered with shade cloth. As long as it is not too cold they thrive with the move. Rarely do I move from inside, directly to the ground, but when I do, also with the white cloth.

If it is bright or cold those first days I will do two layers of AG19.

[PoisonApple]

This will be my first season with LED replacing my fluorescents. I struggled with the right answer by went with a little more mild light due to my seed starts being in a fairly sunny south facing window.I don't have a huge setup, just 10 - 18"x48" shelves, each with 2 of these LED bars. I hop it works out ok.

https://hydrobuilder.com/floraflex-incu ... -of-2.html

[JRinPA]

That's an investment, $640?

[PoisonApple]

That's an investment, $640?

Luckily I got them for a bit of a discount off that at $59. I'm happy to be done with fluorescent lights. I have just never had good luck with the ballasts. I also expanded from 3 shelves to 10 shelves so I would have had to buy something one way or another. These are also nice because they are a waterproof housing so I don't have to worry if I spill some water down over them from the shelf above. Though there isn't a tremendous savings in power consumption between them, they will pay for the cost difference over their lifetime (at current rates), assuming they last 10 years.

[AKgardener]

I find it so hard to find lights they all say the same thing so it’s hard to choose and everyone claims there’s is the best.. I have 2 spiderfarmers to close plant get to much still figuring it out I have these new ones off of amazon there like little sauces so far I have been able to put them closer and they have worked great so I have 4 now.. I will be using them once the seedling get better .. let us know how well the lights do

[JRinPA]

@PoisonApple A shelf with two fixtures, is that 36 watts for two 1020 trays or four trays?

[PoisonApple]

It does 4 trays. My shelves are only 18 inches deep, but I center the trays with a couple of inches of overhang on each side so I can get greater density. Each light has coverage of 1ft deep so it works out to just about perfect for 4 trays. I wish I had 24 inch shelves but I got these wire racks for a song off of Facebook Market place. I have another 2 units of 5 shelves I will probably enlist next year. I’d like to do a few shelves of micro greens once seed starting season is done. I have never done micro-greens but they intrigue me. I struggle with outdoor leafy veggies and would love to have fresh cilantro, lettuce and arugula all year long.

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[JRinPA]

Sounds like those lights were a good investment.

I can do 4 trays, 5 if really squeeze them and rotate them, on the table under two lights. But these are the LED shoplights from HF, drawing 53 watts each, and tomatoes leaves were a little off with them last year. It wasn't just the lights though, I also started them differently with DE. So on the upper shelf I have squeezed a T12 back in with daylight bulbs (paid for years back) that uses 50 watts. The LEDS are good and bright but I don't think they cover a full 20" by themselves. So it still takes two for a 2x4 or 2x5 area. 106 watts instead of 36 watts for the table, then 156 watts (with better spectrum) instead of 36 watts for the upper shelf.

I will need LEDs replacing or supplementing the existing basement lighting, so those floraflex might be a good upgrade for me before next year if I rotate these out. You mention a more mild light. My grow room is the basement. I wonder, will those 36 watts do enough for tomatoes by themselves? Sounds like the are supposed to be? I have not heard the term "cloning lights" before, I'm not in that game.

[PoisonApple]

I think they are good for my purposes being an assist to some south facing windows. I liked they use a little less power and won’t have much concern with burning in this particular situation. I’m definitely not an expert on lighting, but my guts says you’d need higher light density for a situation where you have little to no natural light. Those Spider Farmer SF600 seem like a good option. I will probably look closely at those for my other 2 shelving racks next season since I’ve run out of south facing window ( I have 3, two with seed racks and 1 with dwarf citrus trees).

Sounds like those lights were a good investment.

I can do 4 trays, 5 if really squeeze them and rotate them, on the table under two lights. But these are the LED shoplights from HF, drawing 53 watts each, and tomatoes leaves were a little off with them last year. It wasn't just the lights though, I also started them differently with DE. So on the upper shelf I have squeezed a T12 back in with daylight bulbs (paid for years back) that uses 50 watts. The LEDS are good and bright but I don't think they cover a full 20" by themselves. So it still takes two for a 2x4 or 2x5 area. 106 watts instead of 36 watts for the table, then 156 watts (with better spectrum) instead of 36 watts for the upper shelf.

I will need LEDs replacing or supplementing the existing basement lighting, so those floraflex might be a good upgrade for me before next year if I rotate these out. You mention a more mild light. My grow room is the basement. I wonder, will those 36 watts do enough for tomatoes by themselves? Sounds like the are supposed to be? I have not heard the term "cloning lights" before, I'm not in that game.

[rossomendblot]

I have my quantum board style grow light set at 25 W to cover a 2x3 foot growing area. It's in a grow tent so there is no extra external light. That seems to be more than enough for pepper seedlings until they start going outside during the day in May. I think when I grew micro tomatoes over winter I bumped it up to 35 or 40 W, for flowering.

I start my tomatoes, cucumbers and squash on a south facing window sill in April, and they do really well without any grow lights as long as you rotate the trays a few times a week. The same window sill I have been using to grow microgreens all winter with great results, even with the low light levels.

[svalli]

I have been growing my seedlings with LED-lights many years now and started with some self made and even with floodlight style 4000K lights. Since some tomato varieties seem to suffer from intumescense, I had to keep growing them under regular fluorescent tubes. Two years ago I purchase my first LED grow lights for seed starting, because I got fed up on having so many AC to DC adapters to connect to all my DIY lights and wanted something which connects directly to wall socket.

First ones which I got are full spectrum 14000K tube style lights. https://www.eugardencenter.com/en/surya ... -90cm.html
That cool light makes seedling grow robust with short stems, but still having buds early. Some tomato seedlings still got intumescense and I had to move them under my old fluorescent light.

Last year I ordered couple of other type grow light tubes, which one has UV-leds and the other one IR-leds.
https://www.led-grower.eu/cosmorrow-led ... traviolet/
https://www.hortimol.net/en/tled/30-146 ... ectrum-k14

After testing these tubes did not seem to prevent the intumescense either. UV-leds in that one light are UV-A wave length and tomatoes need UV-B. I then found out that even fluorescent tubes were banned from sales in EU, I could still buy some special tubes which are used for reptiles. These output more UV-B than the regular tubes. I experimented last year to have one reptile tube with the LED-tubes for tomatoes and my indoors grown seedlings have never looked better. I purchased also an second reptile tube, so I can grow tomatoes on two shelves. All other plants have grown well with just the LED-lights and those will be on the shelves with just LED tubes. There are some LED lamps for reptiles with UV-B, but the prices are still too high.

[JRinPA]

Hey svalli that is good info, thank you for sharing.

I'm just not much for carrying trays in an out for hardening off. I put out my onions, spinach, lettuce, and cole crops last evening. I put up a 9ft tunnel house on the raised bed, and draped it with some ragged AG19. Mid afternoon today, and again this evening, they looked fine, even with full blaring sun all day. These plants had the fan for a week or two I guess - I'm sure that helped. I expect the onions would be fine regardless but the leafy plants would have had it rough without shade.
The leafy stuff and most of the onions as well were under 2 HF LEDs and 1 T12 daylight fluro. The other onions were juSt 2 LEDs.

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If it gets really cold some night I might consider bringing them in, but it will have to be below freezing for sure.

[CrazyAboutOrchids]

I read through the replies quickly so this may have been covered but i didn’t see anyone flat out state it, the seedlings still need hardened off. Not from a temperature standpoint but light. Even though your lights may be full spectrum grow lights they still aren’t as full spectrum as good old sunlight and the tender little seedlings get sunburned so bad they die.

Yes, under LED you still need hardening off. But I tell you, under the SF600's my plants grew far better than previous years and the hardening off process was much less than under the T-8's in previous years. I didn't have issues with the light, last year I had breezier conditions during the hardening off process than I have seen before. I think the plants were better acclimated to light or so it seemed, but I guess I need to up my fan a bit.

My changes this year with my SF600's.... tomatoes on a separate shelf, fan on a timer with the lights and maybe kicked up a notch as the seedlings grow. Will report back later with this years results.

[slugworth]

I just had a 4 foot LED light fixture go bad.
Autopsy shows the voltage going to the LED's are actually higher than the input voltage @146v DC if the label on the "ballast" is correct.
I always assumed the led voltage was much lower DC.Maybe they left out the period between the 14 and 6.

[crunch1224]

I use T5's 5,000k and have pretty good success. I know leds are a better way to go but I think I might be onto something. The way I grow my tomatoes are a bit on the leggy side. My tomato seedling plants are about 8 inches to 12 inches taller than others I have grown with better lights. At first I thought wow this is a bad thing they are so tall, but when it came time to plant them into the garden I planted them way deeper and thought nothing of it. As they grew they proceeded to get thicker and stronger. I started to notice that they needed less watering and they withstood heat waves better. They eventually all turned into monster sized plants and had excellent yields. After the season was over I pulled up the plants. The plants had a massive and I mean massive deep root ball.

So having cheaper lights that dont work as well as leds isnt necessarily a bad thing for tomatoes. I did transfer the plants from the starter cells to 4 inch pots while under my lights. They never got root bound and I did have them in front of fans as well.

[JRinPA]

Keep at it crunch.

I don't think LED are better, but often cheaper to run. I seem to bang them around a lot, which I would never have risked before.

I still have my T5HO four bay fixture, but the bulbs are kinda shot I think. But I'm not sure if the ballast/wiring is perfect still. I really didn't want to buy new bulbs just to find out it was the fixture. I never found bulbs for much less than $15 each. I bought the fixture new with bulbs in for around $80...Also, it gets too hot for cole crops. That said, I recall putting 8 trays under just that single fixture. If it was still as bright as when I bought it, I'd still be using it.

I might up pot tomatoes this year, too, been a while for me. This year I don't think it they will be through black mulch, so I will be able to trench them properly again. I actually started some early, some of slicers. BLTs were too late a start last season.