I am new to the world of grapes. I am trying a few different table grape varieties. Soil pH is 7.2. It has been hot and windy the last few days so I am assuming that is stressing them even more. I assume it is a micro nutrient deficiency, at least it looks that way to me. Any other thoughts? Thanks
Any idea if you have had any growth regulator herbicide applications in your area recently? The leaf cupping looks like it could be herbicide damage.
Oh the herbicide thing is definitely a possibility. I live in BIG AG country where unfortunately herbicides are applied left and right. Unfortunately we are all too well versed on this site about Ag applicators that apply products in a haphazard manner. Seems to vary a bit from vine to vine in appearance though. It might just be how each variety reacted to the herbicide drift if that is all it really is. The initial leaves looked healthy on the vines, but they are all new vines this year so I wondered if the initial healthy growth was a result of “good” micronutrient levels within the roots. I guess we will see if they grow out of it. I might try and experiment a bit with a application of foliar micro nutrients on a few and see if that makes a difference.
I’ve seen our weather do that as well. Aphids can cause weird leaf growth but they make the leaves looked stretched out. In this case I think it’s tender leaves and hot sun or glysophate.
Grapes are extremely sensitive to some herbicides like 2,4D. It only takes a very small amount to cause noticeable damage to leaves. That amount of drift can come in from miles away under certain weather conditions.
Well I basically assumed that grapes would be a very iffy crop where I live for the reasons I already mentioned. We do have more and more grape production in our state all the time, but the number of instances where a vineyard receives damage from herbicide drift is also increasing in the news. At this time it is just an experiment on my part so I am not out a lot if they manage to kill them. I guess time will tell.