I have 3 year old grape vines, reliance, concord and a white. They are doing nothing. Every spring they come up looking fine , then do nothing. By the end of the season they drop their leaves I think prematurely and wither away. I spray for fungus but was always told they did not need fertilizer, they would grow like weeds. They are still just a small 2' high bush. I am in the mountains of NC zone 7 with a sandy clay. Guess I always thought grapes were a no brainer, perhaps that labels me.