This will be plenty of space. We have about a 6 foot long by 2 feet wide bed that we plant 4 squash plants in, regardless of the type, so we just space them out within that range. This time around we actually stuck 7 pumpkins in the same space and they are doing just fine. They find the room, trust me, just expect some of the larger types, like pumpkins, to want to space out more. They require lots of training if you want to confine them to a certain space, but it's not hard, just a little moving here, a little moving there.

I just harvested my butternuts this weekend. I had 2 plants in a 2'x4' area of a raised bed. The trellis I used was two 7' fence T-posts and concrete re-mesh wire. I guess the complete trellis was 4' wide x 5 1/2' tall.

The butternuts were fantastic. I did not prune them. I have to admit about August I got busy and quit training them and they took over the cantaloup that were next to them. But that should be chalked up to operator error rather than bad spacing.

I guess the short end of it is that 2'x4' was really perfect for my zone 5 vertical butternuts.

One thing I noticed was the squash on the trellis were more elongated than the ones that grew on the ground. I did not support any of the squash. The vines grew to accommodate the weight and held them just fine. I do the same with my cantaloup and spaghetti squash, no little hammocks.

I have not grown pie pumpkins vertically.