This grape was already planted and growing when I moved into the house so I really have no idea of the variety. Whomever owned the house before me had planted 1 grape vine on either side of each of the posts which left 4 grape vines all growing together in a jumble in really close proximity so I ended up cutting them all down first winter in the place. I let this vine grow and last summer it produced smallish yet fairly sweet purple grapes. Not in any great abundance as the entire vine got cut down but it did produce. This year it has been growing more vigorously and has produced grapes - BUT - many of the leaves are going all bumpy and looking really bad. Anybody have any idea what this is? Are there any treatments for this? Or would I be better in cutting the entire grape down? This is the grape from a distance which gives a sense of its size These are what some, not all, but some of the leaves are doing. Looks awful These are the unripened grapes. You can see that some of the leaves are ok but some have all those ugly bumps. Thoughts and suggestion on how to treat this would be appreciated.
It looks as though your problem could be caused by Grape vine blister mites. They don't do any damage to the growth of the vine or the grapes although they do make the vines look unsightly.
I would not do anything now. Wait till the leaves drop this fall and treat with an antifungal and neem oil after pruning. Spray again before leaves form in late winter/early spring. You do not need the antifungal for the mites but it will prevent many of the problems that affect grape production. The mites in question here overwinter on the leaf buds. Might be good to burn the leaves after they fall but usually the mites are gone from the leaves by then.
Thanks for the advice The grapes do seem to be growing well but lots of the leaves are looking pretty ugly. They didn't have this last summer (which was the first summer I was here). This seems to be a developing matter I've started seeing this past month. Not sure what these grapes are. They were sweet to eat last summer but remained very tiny (but I had cut down all the vines to almost nothing) Thanks Mart and Eileen
The size of the vine has nothing to do with the size of the grape. Vineyards cut theirs back every year to 2 to 4 lateral canes and trim all the current years growth because the vine has already produced. Grapes grow mainly on the new growth each year. Weather and grape variety may be one reason the size is small or possibly it needs a bit of fertilizer. Dry weather will make the grapes small !! But if the vine growth is normal I would not worry much about that although a small amount of fertilizer will not hurt !!
@mart - Last summer we had a record breaking drought here. Nothing much was growing as ultimately there was no water so right from the get go the grape was disadvantaged. This year the grapes bunches are fuller and bigger however this summer we've had more than normal rain. Am probably going to prune it back again this year as the area it was planted to grow in is pretty small and I'm sure if not pruned it'll take over the Japanese maple tree and the entire trellis area.
