About 18 months ago, I moved to a house with a big yard in which some bygone owner of yesteryear planted some grape vines (there are a lot in this neighborhood, which used to be primarily Greek).

I know essentially nothing about growing grapes, and I have no idea what variety of grapes these vines are. They did not bear fruit last summer (our first in this house), but I see copious flowers on them this year. they are planted along a fence in soil of completely unknown fertility.

How do I encourage them to bear fruit? Should I be watering? Fertilizing? Pruning? they are pretty wild and all over the place. Any advice is greatly appreciated!

Also, how can I determine what variety of grape they are?