My Concord grapes are dying before they turn purple!

[user 39228]

So this is the 5th year that my grapevine has been growing and every year I get a really good amount of healthy grape growth in the beginning but almost all of them shrivel up and die before they fully ripen to a the purple wine grape that they are supposed to. This has happened every year around this time (July) and even earlier. I am growing them on Long Island, NY. Please look at the pictures, you will notice how they start to turn purple but then look like they rot out and then finally they shrivel up and fall off. They only spray I use is a very light spraying of stylet oil (this year I only applied once). My soil is very alkaline so this year I attempted to make it a little more acidic by adding holly tone. Any advice would be greatly appreciated, thank you!

 

[balatonwine]

Photos 1 and 3, I would say anthracnose. You are not applying enough of the correct fungicide.

Photo 2 berries not formed due to pollination problems.

 

[BigH]

My vote is black rot for photo 1 and anthracnose for 3. The Iowa State viticulture specialist recommend a dormant application of liquid lime sulfur to deal with my anthracnose problem. Early mancozeb sprays when shoots are 1 to 3 inches helps.

H

 

[KevinL]

My opinion for 1 and 3 Black Rot and Anthracnose. respectively. I had a big problem with both last year until I started a spray rotation this year.

 

[user 39228]

My opinion for 1 and 3 Black Rot and Anthracnose. respectively. I had a big problem with both last year until I started a spray rotation this year.

What are you spraying and what is your rotation schedule?

 

[user 39228]

My vote is black rot for photo 1 and anthracnose for 3. The Iowa State viticulture specialist recommend a dormant application of liquid lime sulfur to deal with my anthracnose problem. Early mancozeb sprays when shoots are 1 to 3 inches helps.

H

I live on Long Island, NY are we in the same region? If not, can you direct me to where I can find the right application info for my growing region? Thanks!

 

[user 39228]

Photos 1 and 3, I would say anthracnose. You are not applying enough of the correct fungicide.

Photo 2 berries not formed due to pollination problems.

What would be the correct fungicide? And how do pollination problems come about?