Crossing never affects the current generation, so the fruits will grow true to type. If you were to save the seed and grow it out, that is where the cross will show.

Just wondering - when you say "put them in the ground" vs keeping in the GH, are you growing in pots or beds in the GH? Depends on variety (if you have small "bush" versions) and if you are hand-pollinating, parthenocarpic, or not, but I think the corn and squash/melons will do better outside in the ground with wind/insect pollinators. Tomatoes will do fine in the GH (provided you have proper support), herbs could go either place but depends on the herb - most herbs are quick to mature enough to harvest, and if you don't mean to overwinter them you could put them outside.

If you provide more details we can help more.

Cucumbers and watermelon are in completely different genuses (genera) so they can't cross. However, the zucchini and buttercup squash could since they are in the same genus but it's unlikely since they are different species. Cucurbita pepo (zucchini) and Cucurbita maxima (buttercup).

What's the outside temp versus the temp inside the greenhouse? That's a big factor.

Rodney

You're in the same zone as I am. I'm in central Saskatchewan and we normally have warmer summers than you, but this year it has been very cold and rainy with no change in sight, June has been 3 degrees C below normal.

The watermelon and butternut squash will do better in the greenhouse. That's a given.

The herbs will likely do better outside, especially if you have cool-season herbs (which most herbs are, except basil). Things like dill, cilantro, chives, chervil, rosemary, sage, etc. should be outside and they can tolerate some frost. Only basil needs to be started indoors.

The tomatoes, corn and zucchini could go either way. They like it warm but not hot. I would keep some inside and some outside, so that no matter how the summer turns out this year, you have something. Corn takes up a lot of space so I would put it all outside.

This post was edited by Slimy_Okra on Tue, Jun 24, 14 at 11:58

I always keep Basil under glass - the summer heat just isn't intense or reliable enough for it to do really well outside.