Grapes Rotting

pittsfordnygardenerJuly 23, 2013

Many of my grapes seems to be rotting or infected with something. On this same vine there are some bunches that look fine. But the majority seems to be not doing well.

It has been a very wet summer. But this seems to happen every year.

Any ideas?

Thank you for reporting this comment. Undo
Scott F Smith(6B/7A MD)

Black rot is the most common cause of that. Sprays in spring are required to clear it out of the vineyard. It is hard to treat organically; copper is probably the most effective spray. If you use synthetics then Immunox does a good job on it. Different grape varieties have very different degrees of susceptibility.

Scott

    Bookmark   July 23, 2013 at 7:16PM
Thank you for reporting this comment. Undo
Dan.NY

The other spray for this is Nova Rally. Strong stuff. Recommended by Cornell for black rot, for what its worth.

    Bookmark   July 25, 2013 at 4:03PM
Thank you for reporting this comment. Undo
Scott F Smith(6B/7A MD)

Dan, Immunox, Nova, Rally, and Eagle are all myclobutanil, the same stuff. Home growers can generally only find Immunox readily available.

Scott

    Bookmark   July 25, 2013 at 5:17PM
Thank you for reporting this comment. Undo
nickl(Z7a NJ)

Black rot. The controls must be correctly timed. Two sprays of mancozeb (new growth and pre-bloom) followed by two sprays of myclobutinal (post-bloom and pea sized). The first (new growth) spray is not as important as the next three, which are absolutely critical. But if you can get the first spray in, it would help.

The reason for the program is that while mancozeb will completely control black rot by itself, it can only be applied up to 66 days before harvesting, Depending on the variety, you may be bumping up against that limit by the time of those third or fourth sprays. Hence the switchover.

This post was edited by nickl on Tue, Jul 30, 13 at 0:30

    Bookmark   July 30, 2013 at 12:14AM
Sign Up to comment
More Discussions
Too new to know...is this root acceptable?
I'm new to Orcharding and to GardenWeb (what an incredible...
GuardinDawg
huge raspberry bush!!!!
Help! My husband and I have a humongous 6 foot spread...
satami00
Source for Hidden Rose Apple?
Looking for a tree or scions but seem to be coming...
jsvand5
Help... pest eggs on orange fruits
Orange fruits got quite some eggs on them. I have searched...
funlul
Pictures missing!
Have you noticed, since Houzz took over allot of pictures...
Konrad..just outside of Edmoton Alberta
© 2015 Houzz Inc. Houzz® The new way to design your home™