Other treasures to collect...

Isn't this sweet? This is called 'Heartleaf hibiscus'. It is a native of Texas, grows very easily from seed. The leaves are kind of furry. It seems we grow more and more natives in our gardens now.
This is Jatropha. There are many, many varieties of Jatropha, and I am not sure which botanical this would be, but this is the one we grow in our gardens. It will freeze, but usually will come back from the roots. This one makes a little ornamental tree, blooms most of the summer. I have seen it get to about 10 feet tall, with some protection in winter.

A lot of bio-fuel is being manufactured from some varieties of Jatropha now, I think, and it is a big part of the economy of some Third World countries. Sumatra comes to mind, for some reason.

Foxtail fern is related to the Asparagus fern, only more 'civilized'. It makes little white berries, and does have prickles that hurt if you step on them, but WHY would you be stepping on them?! They will multiply rapidly, and they will get big, so we try to allow for growth when we plant them.
We have very sweet soil, and the ferns seem to like it. I don't know what they would do in a more acidic soil.
Take over the world, probably.

All these things are spectacular when grown with Sweet Potato 'Blackie' or 'Margaurite'.
Also, 'Aztec grass', a form of lirope, is a great companion for any of them them. They are happy in a bit of shade, if necessary.