I am totally new to grape vine growing but I want to avoid some mistakes and this is the main reason I joined this community. I planted my first grape vine in June of this year. It’s Himrod (Vitis labrusca). I planted it between two, 7 feet high poles, that are 8 feet apart. There are 2 wires between the poles, 1 about 3 feet above the ground and the 2nd one about 6 feet above the ground. At the end of July I removed two weaker shoots and the strongest I chose grew already to almost 5 feet high. My goal is to have 2 shoots going in both directions on the 1st wire, and then 2 shoots going also in both directions on the higher wire. I live in Pennsylvania in zone 6a. So my question is when can I start to train the vine or when to cut the main shoot. I read somewhere I can cut it to about 5 feet once it grows to 7, 8 feet high even before winter or rather at the end of summer. This is the 1st year so I want to start without any major mistakes. Thanks for any advice.