Growing Squash and cukes vertically

The best cucumber that I know of is called BURPLESS TASTY GREEN. Produces
abundantly the entire growing season. Don't know if string can handle the
weight. Maybe something thicker (we recommend baling twine - available at farm supply stores - JK).

As far as squash goes, if you mean Summer Squash, try Trombone Squash
(google it to find a source and picture). It is very prolific but again, you
will need something heavier than string. It is very aggressive so unless you
are feeding a whole lot of people, two plants will be plenty.

With both the squash and cuke, you will have to help them along and
possibly tie them up to help them climb.