White Tops

[mfisher1301]

Any idea why my tops are turning white?283928283929283930

[silent leprechaun]

Could be burning or bleaching.
Are your lights too close ? What lights are you using ?

I would guess bleaching.

[mfisher1301]

I'm using 90w UFO LED's. I have 8 in a 6x8 room. Lights are 12 to 16 inches off the tops. What causes bleaching?

[Weezard]

Your pictures do not expand.

But, that looks like light-bleaching to me.
It happens with good LED arrays.

First, they stop growing vertically, then they bleach.
You need to raise the lights, they look much brighter to the plants than they look to us. :D

Aloha,
Weeze

[mfisher1301]

Will they go back to green? Should I get a light meter and will that help?

[silent leprechaun]

I use LED too. It is quite easy to bleach them as the LEDs run cool. Its easy to think you can keep the LED close as the plants wont burn.

The plant will continue to produce bud but I wouldn't smoke the bleached part. It is damaged and wont become green again in that area. But the bud will continue to grow.

Certainly move the light higher or maybe start some low stress training on the plants. This will allow the LED to shine on more of the plant. You will have more tops too which usually means more yield.

Good luck

[Weezard]

I use LED too. It is quite easy to bleach them as the LEDs run cool. Its easy to think you can keep the LED close as the plants wont burn.

The plant will continue to produce bud but I wouldn't smoke the bleached part. It is damaged and wont become green again in that area. But the bud will continue to grow.

Certainly move the light higher or maybe start some low stress training on the plants. This will allow the LED to shine on more of the plant. You will have more tops too which usually means more yield.

Good luck

That is excellent advice!
The tops will not recover.
(Though, I'd smoke them just for gits and shiggles)

Get some soft, cotton twine and start tying the tops down.
The newly sprouted flowers that result will give you a "sea of green".
The most pragmatic method for growing with LED arrays.

Aloha,
Weezard

[silent leprechaun]

Thanks Weezard :)

I noticed a tiny amount of that on one of the tops of my last crop. I just tied it down and it stopped the bleaching.

I found that LSTing is vital in LED growing to get good light penetration. My light rocks but if the canopy is too dense, or the tent too cramped, the lower leaves can slowly begin to yellow.

Take care.

S.L.