When to wean them off artificial light?

14 years ago

Sowed Feb.22, so most have been under lights for four weeks now, (16 hrs.on).

One row of flats is under 24 hr. light, can that be detrimental?

Understanding the importance of copious amount of light at this stage, I am wondering when the time would be best to set them into light from south facing banks of windows?

I am wondering if a specific timing brings the best results.

Would the sun's light benefit them more even tho the time exposed is reduced, or would they bolt like some mutant form of the Elongated Man in the comics between now and May at harden off time?

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Comments (9)

digdirt2
14 years ago
Normally they aren't removed from the lights until you are ready to harden them off for transplanting to the garden - say a week to 10 days before. Otherwise they just go leggy. Garden time is still some time away for you I think. Say 6 weeks, right? But 24 hours isn't really needed. 12-16 is sufficient so you could always cut them back to that.

Dave
windclimber
Original Author
14 years ago
Thought so, thanks,
I have the majority under 14 banks of duals and utilized an 8' hard wired flouresent I cant' regulate with a timer.

I'm away from the location so can't just flip the switch.

What detriment do you see as to the excess exposure?
Perhaps some adverse effect during the growing season?

Tom
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digdirt2
14 years ago
For strictly seedlings (no blooming/fruiting stuff) I don't really see any detriment other than maybe a bit more soil drying, more heat, more water, more electricity. I've done it all 3 ways - 12-16-24 with some inside before they could go out to the greenhouse with no really notable differences. Finally just settled on 16 as a nice compromise.

Since you have a light you can't put on a timer do a comparison with some on a timer for 16 - you got time yet ;) - and see if you note any difference.

Dave
wordwiz
14 years ago
A notable research study showed that 24 hours of light had a detrimental effect after several weeks but a guy last year used them on peppers for about eight weeks and he got a much better growth than those under ligh-ts for 16 hours a day. There's a thread in the Growing Under Lights section with photos.

Mike
windclimber
Original Author
14 years ago

In the process Dave,.... noting measurements and differences in the log compared with ones sown at the same time under two different type bulbs.

Only problem with results may be they have more air on them constantly compared with the rest that are breezed with an occilating fan.
Keeps my ballast cooler I guess also. The others have a break as the fan returns across them.

I'll check out that thread Mike, thanks

Tom
lottesgarden
14 years ago
For what it's worth, I sowed my seeds a week before you on Feb. 15 and have had them under lights for 24 hours since germination. As I move them to gallon pots, space is becoming an issue. The next few days are forecast to be 55 at night and low 80's during the day, so I just said what the heck and put them all outside yesterday. (I'm in Charlotte, NC).

They have a little sun scald today but they're still perky. I'll let you know how it works out if you're interested; this is my first year starting my own seeds and I'm amazed I've gotten as far as I have :)
rad1
14 years ago
What does sun scald look like? I just put mine out and have these ash looking spots on the leaves.
lottesgarden
14 years ago
Here's a photo, rad1. They definitely got too much sun and the larger leaves are looking sad. I think they're going to be OK, though. The new growth in the center is very healthy. HTH.
anney
14 years ago
Link below gives information about the need to harden off your seedlings.

Here is a link that might be useful: Hardening Off Transplants -- Bracing Up

When to wean them off artificial light?

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digdirt2

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When to wean them off artificial light?

Comments (9)

digdirt2

windclimberOriginal Author

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wordwiz

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