No Hardening with LED

[mobiledynamics]

I'm not sure where to post this. In the SS or the general forum...

I observed that when I took my seedling off my new LED lights, they seemed less stressed. The plants were healthy though - bushy foliage, slow elongation of growth (maybe more squat and bushy)....

Anyhow, I did a test this year. I did have some backups in 1G if my test failed. I did not do a full slow harden off transition cycle. I did put them on my covered porch for 2 days just so they got acclimated to ~fresh air~. I even have some some very small transplants as well - which got a late start on germinating.

All of them fared fine in the sun, with no leaf burn. We even had 2-3 days of abnormal record setting temps that hit like 15-20 degrees higher than normal. Would someone concur the same and say maybe the LEDS due to the direct light played some role in the fact that I did not need to do a full harden off ?

[Harry Cabluck]

This is worth a looksee if interested in use of LEDs: https://fluence.science/blog/redefin...ewsletter-2018

Interesting article.

[Nematode]

Mobile,
What is your led setup, brand, wattage, spacing, height etc?

[Cole_Robbie]

That is a good article.

LEDs do not contain UV light, which I would think is the most important part of getting them used to real sunlight.

[Koala Doug]

Originally Posted by Cole_Robbie

LEDs do not contain UV light

Most LED lights do not have UV... but some specialty grow light companies do offer UV versions. It's pretty uncommon though.

[rhines81]

Originally Posted by Cole_Robbie

That is a good article.

LEDs do not contain UV light, which I would think is the most important part of getting them used to real sunlight.

I agree and that can be an issue for not hardening off. I hate hardening off though, but I try to plant out on cloudy days if possible. I've had white leaf plenty of times, from UV burn but nothing tragic. I don't think I ever lost a plant from not hardening off... they just get ugly for a week or so. The more cloudy days in a row after planting the better. I've done the whole hardening off routine several times and it is just a hassle (I'll usually get them outside once or twice for a few sunny hours the week before planting though)
I also use fans indoors, so that makes them used to some wind (not gusts though).

[Nematode]

Cole, that was my thought.
But I was wondering if the high intensity alone could induce a uv protective response in the plants.
It is not obvious to me why uv protection in plants would be decoupled from overall intensity.

[uzlaguzla]

If grown in a greenhouse, do tomato plants need to be hardened off?

[Cole_Robbie]

Originally Posted by uzlaguzla

If grown in a greenhouse, do tomato plants need to be hardened off?

Not for the sake of UV rays, to which they would already be accustomed, but possibly for wind or cold temperatures, depending upon the conditions in the greenhouse in which they were grown.

[clkeiper]

I have a friend who has LED growlights for all her overwinter plants. that is the only light source her plants get and they are beautiful, dark green, compact... just all around nice plants. I get to swap plants with her every now and them and I never worry bout them not being quality plants. I put them right in my greenhouse and the never look like they are keeling over.

[DonDuck]

What is the story on LED equipment to purchase to replace T8 and T12 fluorescent fixtures with LED fixtures including sources and cost? I will do some more reading but I am thinking about replacement for 2020 season.


Thank You!

[clkeiper]

Don, there are a bunch of YouTube videos on the conversion of them.

[SQWIBB]

Originally Posted by DonDuck

What is the story on LED equipment to purchase to replace T8 and T12 fluorescent fixtures with LED fixtures including sources and cost? I will do some more reading but I am thinking about replacement for 2020 season.


Thank You!

Do it, your plants will love you for it.



Cost is minimal and you'll have to use non-shunted tombstones or break the shunt, so the only cost would be the bulbs.


These bulbs are 4 for $40



You can order non shunted tombstones on line or just break the shunts on your existing tombstones.


Non Shunted tombstones.










I just finished mine earlier this year then opted for other lights, so this was disassembled and the bulbs used for my fish tanks.






Your best bet is to try and find 6000k or 6500k bulbs with the power on one end.
Remove the ballast and save the wire (cut wire close to ballast, leave just enough wire in case you want to reuse the ballast)
then you rewire the tombstones, one side is hot and one side is neutral, then pig tail all the hots together then pigtail all the neutrals together, you can then put a switch on the hot side if you want a switch, then wire the pigtailed wires into the lights existing cord.


Here is where I added a wire to the other side to an existing tombstone.








I have done all the lights in my shop this way and this one over my work bench I use for plants that do great. I take this down when the plants go outside.

[SQWIBB]

I switched over to these







Then after a weeks growth comparing lights, I decided that the investment in yet another set of lights was warranted.




,






And these lights do have UV and IR






I just want to put this out there so folks can maybe learn from my costly adventure into LED grow lights.