Tree-wise, I am most impressed by black mulberry (morus nigra). Incredibly fast growing, very useful, but don’t take just my word for it. Read this:
Maypop (passiflora incarnata) is native and volunteered rampantly in my space. I left it mainflh because it’s the host plant for the gulf fritillary butterfly, which were fluttering around my garden all summer.
Mayhaw (crataegus spp.) also grow well and are native. I have one tree. It’s not as fast a grower as the mulberry
Pawpaw (asiminia triloba) is what I’m missing to to complete the “trifecta of forgotten country fruits”.
Roselle ‘Thai red’ (hibiscus sabdariffia) grew as an annual, grew fast and very large, and was quite a stunner vistually. The leaves were sour and I know they are eaten as a vegetable in other countries. I did not get harvestable calyxes before first frost, and I think this is because the plants got too much sun. I think this is a decent mulch plant, but it’s very woody. I bought the seeds from Baker Creek.
I grow tomatoes every year (which makes three years by the time of this post) and they’ve been heirlooms and they usually croak by August. I attribute this to mineral deficiency. (That’s what I tell myself.)
Rubus spp. (Blackberry, raspberry, wineberry) grow in my hard without care. Raspberries get promoted to a garden bed (though they tend to grow outside of it as well). I got about a gallon of raspberries at first flush last year. We froze them and ended up turning them into a raspberry tincture (like lemoncello, but raspberries instead of lemons). My neighbor does not appreciate having to kill the Rubus invading her yard underneath the fence.