Nobody has mentioned planting something to eat. You can raise a little food stuffs in planter pots even. And grow some around flowers in their beds. Then there's dandelions that can be dug up, cut low and replanted in pots or planter beds where dogs don't get to.
Onion roots can be replanted and re-grow for the rest of your life, as do most all of that family. Tomatoes and other veggies can be planted..save a few seeds of some you buy.