more problems, dried, brittle leaves

[mtbazz]

These are three week old blueberry/texas timewarp seedlings. They went straight from being popped into happy frog, and have been watered with RO water for the most part (sometimes I dilute my very hard tap water with RO at a ratio of 1/3 tap to 2/3's RO).

They are under a 4 four foot, 6 tube HO FL lamp that I did have 2-3 inches above the seedlings until I noticed some signs of light bleaching on a few and than I moved it back to about 6 inches.

Any ideas what caused this?

 

[Bush Dr]

Heat stress ..... the leaves curled up to stop evapoaration

 

[PermaBuzz]

fluoros shouldnt cause heat stress unless the leaves are touching the bulb.
I'd guess its your water. Be consistent with adding the hard tapwater. All RO water
should have a little hard tapwater mixed in. !/3 tap could be way too much. Depends
on the ppm of the hard water. In my case, 12 oz hardwater per 5 gals of rainwater is all I need to add but my hardwater has a ppm of 1000+

 

[EvilTwin]

mtb,
Those leaves are dry and brittle because they're either dead or dying. Either too much nutrients for the age of the plant...or somehow the ph is way off.

Young plants should go into a very mild mix. Those leaves won't repair. Just give water till they look like they need some food. Green lightening up or a hint of yellow...
ET

 

[GroovyFeeling]

i would say to little light or to much neutrigents... looks very darkgreen and to well feed ... perhaps to little light to use up neutrigents?

 

[mtbazz]

Thanks. for the replies. At the moment Im leaning towards having the light too close, as I have one seedling that has clear signs of light bleaching. Some searching on the web has found other incidents of T5's being too close harming young plants and other varieties of plants.

The soil and water pH is right around 6.9-7.0. Thats within the correct range is it not?

As for excess nutes, they have not been fed at all in the three weeks since they have germed, and I dont believe that happy frog is too rich of a medium to start seedlings in, Ive started dozens in the past using happy frog with no probs (they were all outdoor, this is my first indoor op in about 4 years).

 

[EvilTwin]

mb,
In the picture, your effected leaves are on the bottom. Light too close would affect top leaves. Logical?

Soil ph range optimally is a little lower then that. 6.3 to 6.9.

I've seen many growers burn young plants from a hot soil mix. But you're the one that's there with the plants...so good luck. They'll recover.
ET

 

[mtbazz]

I guess that does make sense EvilTwin. Im just a little confused because this is the first time Ive ever had these issues. But I guess a new house = new problems.

 

[BigLaughter]

Sorry to bump this thread.just had to ask .....

i would say to little light or to much neutrigents... looks very darkgreen and to well feed ... perhaps to little light to use up neutrigents?

So does this mean that if the leaves are dark it can (but doesnt have to be) a sign that one is adding a little to much nutrients?
Also, does the light effect how much nutrients the plant needs?

 

[hazy]

Yes to both questions.
Less light=less growth=less nutrients

 

[BigLaughter]

Ok, thanks hazy. That was new info to me. Preciate that.