Why are my grapes on vine covered in white powder????

Question

Why are my grapes on vine covered in white powder????

Answer 1

Its probably powdery mildew.  Treat it with a fungicide.  Try to water the plant in the morning giving the leaves time to dry out during the day as wet foliage at night allows the fungus to grow.  You can't control what the rain does but you can control what you do.

Answer 2

This is probably mildew.

Treatment is best in spring before the vine really gets growing - so that you are on top of the problem & can treat it before it is too well grown to get at it properly.

Ask for the appropriate treatment at a good garden centre.

Answer 3

Sounds like powdery mildew, see link:

http://plant-disease.ippc.orst.edu/disea...

Answer 4

Grapes that have a film/haze is probably what is called natural fermentation ( or yeast) that is of course if you meant the fruit it's self.  Grapes are naturally little producers of wine..

Open the link below for more about the wine making grapes

Sugar is added for flavor and extra yeast for more kick!

http://www.khendron.com/index.php?option...

If the leaves have white powder it then it is probably powdery mildew.  If it is a severe case it can be on the fruits as well as the leaves.

Grape -- Powdery Mildew

This link has pictures of what it looks like

http://plant-disease.ippc.orst.edu/disea...

Orthos Sevin 5 % or 10%  (or it comes in liquid form )for a small vineyard would be a good choice to use.  It is also used for insect control.

http://www.yardlover.com/products.php?ca...

Answer 5

I have a sneaking suspicion you have not removed this powder or attempted to remove it.

It is not powder but natural protective coating (almost like a wax) grapes have on their skins. As they mature the coating becomes lighter and lighter (more transparent) but never completely disappears. It is more obvious on darker grapes than lighter ones.

Go to your local super market or farmers market and you will see – all grapes have it. Sometimes it disappears when they are washed and still wet but as they dry the white/gray translucent coating returns to different degrees as they dry. It’s nothing to worry about.