Flourescent lights

North Hills, CA

I'm using VI Tech 93f T10 bulbs
6700K color
3240 Lumins
40 Watts
4800 hours life

The bulbs are a couple inches above my sprouts.

My sprouts do great until they start to grow about their third set of leaves.

Then they get purple spots on them about the size of a pinhead.They look like they got overspray from paint on them.
Shortly after they turn purple from the ground up.
They stay that way for a couple days then they start to drop their leaves or get sick looking.
The sprouts I have that are supposed to be purple turn a very shiney black color and don't go bad as quick.
If I take the plants out from under the lights they loose the purple and turn yellow and the leaves drop off.
It's like the plants are addicted to whatever spectrum of light these bulbs put out and they go into shock if they get put into sunlight or any other light source.
I've tried putting the plants in shade outside,in total dark for a while then only short periods of shadey sun,and under 3 different kinds of other flourescent lights(Philips plant and aquarium bulbs,Philips Ntaural Sunshine,and Otts full spectrum).
The plants don't like any of them so far.
Right now I'm putting 1 bulb VI Tech and 1 bulb of one of the other bulbs in my 2 bulb fixtures since my plants seem to go into shock if I just switch lighting all at once.
It hasn't been long enough yet to see if the plants that lost their leaves will recover from their leaf loss.
I've never had a problem with lights like this before.
Has anybody else?
I'm thinking that maybe the V Tech bulbs put out too much ultraviolet light and my plants are addapted to trying to live with it.
Maybe there isn't much infared light so when they get under other light sources the leaves aren't equiped to process it and the plant drops them to grow new leaves that can.
I'm just using ultraviolet as an exaple,it could be the other way around.
If I remember right plants only use mostly infared and ultraviolet light.
I've also tried cutting down the hours of light my plants recieve from 18 to 12 but if I cut it down more than 2 hours the plants start to loose their leaves again or start lookig sick.
It's like they are addicted to the light but the light is burning the plants out.
You've never seen a sick plant until you've seen these plants.Super shiney purple/Black to Yellow with a hint of green in a matter of hours.
I think I have the worlds Blackest Black Pearl and Black Scorpion Tongue ever grown.
I have some plants in a south facing window with these lights over them that I was turning on for a few hours aftr dark to give them 18 hours of light.They still turn purple but don't seem as addicted.
They just went into a holding mode when I stopped turning on the light at night when the ones that only get the V Tech lights started acting wierd.
It's got to be the lights causing the purple coloring on my plants because when I water and a drop lands on a leaf.when the water evaporates there is a spot where the water was thats not as dark purple.
The spot turns purple after an hour under the lights after the water dried up.Water must not let the spectrun of light causing the purple color through to the plant.
Possibly a reason to think it might be ultra violet causing the problem.Red can pass through about ten feet of clear water(acording to articles I've read about fishing lurecoloring).Whatever color causes the purple can't pass through a drop of water...

Anyone ever had this problem?
I've never heard of it before.
I thaught plants getting the wrong light usually got leggy and yellow and eventually died.
These guys turn Purple and so far haven't died but loose almost all their leaves.They just started doing this so I don't know ifthey will die or not yet.
Actually before they turn purple they look really strong.
I have a pequin thats got 5 or 6 sets of leaves on it thats only about 2 inches high,3 inches at most.
It's trying to grow branches too on such a small,Young plant.
It looks like a plant that would be twice as old as it is.

I took it out from under the lights before it got addicted I guess.
It seems like the plants I put somewhere else before this problem started are doing ok.
They weren't sprouted under these lights.
I'm nearing the end of my sprouting so I'm not rotating plants around from the window to the lights as much anymore and the last plants are always under the lights.
Before I had too many sprouts to fit under my lights and I rotated plants from place to place .
,so all got the artificial light every so often when they looked like they needed it.

Any advice?

Frederick, MD(Zone 6b)

I'm sorry I can't think of anything you haven't already tried... that's just too bizarre!

(I'm sticking with my "ordinary" cool fluorescents!)

Durhamville, NY(Zone 5b)

For a fluorescent to put out more UV it would have to be made out of different glass. If you think it's UV then I'd hold something that was glow in the dark near it. If the lamp is putting out a lot of extra UV it should make the glow in the dark item glow much brighter than a plain fluorescent. The other thing you can do is put a piece of window glass between the lights and plants to see if it makes a difference. Ordinary window glass is opaque to much UV.

North Hills, CA

I have noticed that some of the plants in the sprouters with the covers on look like they aren't growing as fast as the ones that I took off the cover because the plants were starting to get stems that were getting S shaped because the top of them was against the cover.
So plastic must stop some of the light thats comming from the bulbs from getting to the plants.
Actually when the cover is on they are like plants that are too far away from the light,
The more I mess with these lights the more I think it's an ultra violet problem.
I'll have to research Ultra violet in plant growth.
It must effect a plants chlorophil production somehow-turn purple instead of green.
Usually,in my experiance, if a plant turns purple in places it just means it's getting lots of sun and it's a good thing.

The information I have just found says that the higher the color temp. of a flourescent light,the bluer it is.
Sun is between 5000 and 6000 K.These bulbs are 6700 K.
A lot bluer than natural sunlight.
The Philips bulbs are 2700 K and 5000 K color temp.
I think I'll put the lowest numbered one in with the V Tech one and see what happens.It should add a lot more red light to the mix.

The plant and aquarium light is the redder of the bulbs I have.
It makes sence that since ultra violet doesn't go through a lot of stuff a plant and aquarium light manufacturer would only try and give plants what they can survive on.
Most other bulbs I've just looked at are around 5000-5500 K,closer to real sun.
Cool whites are around 3000 K.

I was using cool white but this year I started sprouting peppers in Dec. and cool whites weren't good enough light to keep my plants happy for as long as I needed them to be under the lights.

Once my plants got old enough they wanted different light.
These bulbs are almost equal to some halides in the color range of light they put out so I thaught I'd give them a try.
They are a lot brighter than any flourescent I've used.
I think they are either putting out too much of some part of the light spectrum or not enough of a part.
I'm hoping I just substitute a couple bulbs with another kind and get the right light that the plants want.

Back in the dark ages when I was playing with early hydroponics the only grow lights you could get were growlux and if you didn't have them you had to use cool white and an incandescent light bulb to get the right light for plants.
I think you needed 1 incandescent bulb for every pair of cool white then a couple more of one or the other of them to get plants to bud.I forget which bulb put out what light.I think it was infared for the incandescent,not sure.
Heat was a real problem back then.
Old transformers for flourescent lights used to get hot and so do the incandescent lights.You also used to have to use a ton of them too.

This year I tried starting plants really early to see if I could get a couple crop rotations in.

I started 1/3rd in dec. hoping the first ones would be done around July.By then the ones that are sprouts now will go out.
Then I have a lot of C.Baccatums I'll put out for winter(not much winter in Cal.) along with my Rocotos and Manzanos.
I was hoping to get about 300+ varieties of plants this year.
Doesn't look like it's going to happen.
My early stuff has ripening pods on it now but the replacements that are under the lights now aren't going to be ready on time.
They will have to recover from what they are going through now and then play catch up.
I still don't know if they will survive yet.
Some are sticks with a couple mini sprouting leaves growing on them.

I just found some info on fluorescent bulbs so I edited my post.

This message was edited May 31, 2008 4:33 PM

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