I put in a couple cucumber plants I started from seed this week. They look happy except for their white leaves. I read it is too much nitrogen - if that is the case how do I help them before they die?

Thank you!!
Janelle

Janelle,

Could you post a picture of one of the plants, including its planting spot? There are several things that might be happening, but unless we can see it any advice we could give would pretty much be just a shot in the dark.

I thought about that after posting :)

Here are 2 pics.

I also had trouble last year with cukes. Turned out to be powdery mildew.

That does look like powdery mildew. Trish would prescribe spraying it with milk to control it. Daconil would be the non-organic control method.

Here's a thread that I found helpful on the milk remedy. The thread "Mildew" in Fighting Mildew Naturally

I used it successfully with applications applied once every few days.

Thank you all so much! I will try milk in the morning on my plants and see what happens!

Doesn't look like powdery mildew to me. It seems to be more along the lines of nitrogen burn or starvation and possibly combined with environmental factors (hardening off, sun burn, etc.)

See how the cotyledons in the second pic are whiting out, basically used up? (Normally they'd wither and fall off...but!...) Notice the older true leaf in the first pic is showing signs of burn/whiting but yet the newer leaf is nice and green? Normally a plant will send available N to its new growth so the older leaves will suffer from lack of N. Powdery mildew would attack all the leaves, not just the older ones.

And also see how the "mulch" around the plant is fresh, probably still breaking down and stealing the N from the tiny root system of the plant? This would also create heat that could physically burn a plant not properly hardened.

The plant may be suffering from not being hardened off properly, which, again, may be why the cotyledons and the first leaves are showing signs of scald (whitening) while the newest leaf is green, the latter having grown under the sun and hardened off naturally.

Powdery mildew, and downy mildew, will appear on the surface of the leaves, appearing as something you can nearly rub off with your fingers. This looks more like something within the plant tissue.

Shoe (always wondering....)

I agree with you, Shoe. That one nice green healthy leaf looks good. While the milk treatment probably won't hurt, maybe look at the leaves with a magnifying glass and see if the white parts look fuzzy or not. If it is powdery or downy mildew, the leaf surface will look fuzzy.

Otherwise, I'd treat with some very dilute fert - maybe 1/4 strength of a soluble type - weekly for a couple of weeks and watch how the new growth comes along.

Shoe the expert to the rescue. There's some excellent advice there.

NO...please. No expert here, just trying to be observant. After all, what makes gardening so fun and holding our attention is we'll often continue to wonder "just what happened" or "wonder what caused that?"! It keeps us in awe of Ma Nature, eh? :>)

Shoe (grateful for the compliment) (and hoping to hear back on how the cucumber plants rebound!)

Thank you again for all your suggestions. I tried the milk, because I figured "why not" even though the leaves were not powdery. Either way. I think it was a short of shock. The plants are happy now and adjusting wonderfully. The new leaves are green and healthy and the plants are growing.

Thank you again!

That's great news, Janelle!