FlytrapCare Carnivorous Plant Forums

Hello, I've been using 4x20watt 6500K LED tubes for a few months now. I noticed that my sundews doesn't do well when the lights are too close to the pots. Initially I placed the lights 2 inches from the pots because they doesn't produce any heat.
The sundews turned red in a couple of weeks but growth stopped completely. I thought the lights weren't strong enough, so I decided to add two more tubes, but the same issue.

I waited for about two months, the plants looked okay, but no more growth. Even worse my Alicia seedlings almost two months after germination were blood red with only 2 leaves. They froze in time.

Finally when I decided to lift the tubes to about 4" inches, my sundews not just resumed growth but also started flowering. I'm wondering if anyone experienced something simmilar.

I always wanted the highest lumens per square foot and followed Barry Rice's website taking light readings with my DSLR camera, so I can obtain the highest shutter speeds possible. I got a shutter speed reading of about 1/400 on my camera when the lights were 2 inches from the pots (probably about 2000+ lumens per square foot), but to be honest I don't care about these values anymore, my sundews seem to do even better at lower lumens per square foot. I'm wondering if I should lift the lights even more to about 6".

Do you feed them? I noticed some of my binata froze in time as seedlings because I didn't feed them. Just my two cents

Yes, I feed all the mature plants with blood worms. Once at two weeks. They had drops and beautiful coloration but stopped growing completely for months when the lights were too close.

Speaking of the seedlings, I haven't had the chance to feed them, they just slowly starting to produce dews since I lifted the lights. Most leaves only have two drops yet. I think it's better to wait a week or two.

I found a similar user via Google search noticing something similar:
http://www.cpukforum.com/forum/index.ph ... ment=80200

LED lighting for CP is a relatively new technology and many if not most of us are still on the learning curve. I keep my 16W LED lamps within 3 inches of the plants, my 75W LED within 8 inches, and my 127W LED (MarsHydro 300s) within 18 inches. I change the plant to light distance after I see unhappiness in the plant. Like most growers, I'd suggest as close as possible. But that's only a starting point. Watch your plants. They'll show you if you need to make a change.

Good growing,
Mike

It certainly is possible to provide too much light, or too much heat. Most plants will completely saturate their chloroplasts at about 75,000 lux (about 7,000 lumens per square foot) and can't use any more light than that - more is not going to help and may be detrimental. In addition, even if the LEDs themselves aren't very hot, strong light will heat up the pots. It's probably not enough to cause a problem here but you never know.

the D. aliciae i have with broad-leaved D. capensis under t-5s really seems to express itself best when the lights are nearly 2 feet away from the plants. granted, you don't get the "jewelry" of super huge dew drops, but you get bigger plants which still have dewey leaves. the leaves are green with red tentacles, and the red-leaved capes also keep their red colors well. it also keeps the temps down when you have cool air coming in from the sides (i use a small fan on the same timer as my lights)

the idea of sundew vigor vs sundew beauty is made complicated by the human appreciation of the dense, shiny dew drops on ruby-red leaves. i often wonder what they look like in the wild.