If you have time & not too many grape plants, you can hold a cottage cheese container that contains water & a drop of dish soap (about half full) under the beetles. Touch them & they will usually roll off the leaves & into the water. If you have too many for that, Raid flying insect spray works well on beetle clusters. Seven or Eight spray works well also. I always spray some Raid into my soapy water when I start just to make sure they don't escape. After you're done catching them, spray them again & after a few minutes they make great fertilizer in your flowerbed or compost bin.
If you have time & not too many grape plants, you can hold a cottage cheese container that contains water & a drop of dish soap (about half full) under the beetles. Touch them & they will usually roll off the leaves & into the water. If you have too many for that, Raid flying insect spray works well on beetle clusters. Seven or Eight spray works well also. I always spray some Raid into my soapy water when I start just to make sure they don't escape. After you're done catching them, spray them again & after a few minutes they make great fertilizer in your flowerbed or compost bin.