My sister in California has concord grapes but they are only producing very few grapes. Do you thinks she needs to prune them and if so how? June
There are Concord, California Concord, and Seedless Concord (and probably a few others). The original Concord is not very popular in California, but that may be because there are so many other choices, rather than because of poor performance. In it's native New England it does very well and there aren't so many others to choose from. In spite of all that, if it's growing at your sister's place, she can improve the fruiting by pruning hard during the winter (do you actually have a "winter" in Ca?). This is my favorite grape pruning page for the home grower: http://mtvernon.wsu.edu/frt_hort/grape_pruning_basics.htm Ralph