More on Amaranths
Buying: If you intend to use the greens or use the beets raw select small ones which will be more tender. If the beets will be well cooked you could use larger ones but much above a pound you risk them becoming stringy.
When buying beets without leaves, make sure they have some stem stubble at the top end, and preferably with root still on. Beets trimmed without any stem stubble have probably been in storage way too long and have lost flavor. They will also bleed out their color during cooking.
To store beets, cut the greens down to about 1 inch and keep in a refrigerator crisper, unwashed and unwrapped or wrapped loosely in paper. They'll last several weeks.
Greens: Beet greens are edible, particularly when young. Tender ones can be used raw in salads, larger ones stir fried or sautéd in oil or with bacon. They are similar to spinach but can stand much longer cooking without becoming mushy down.
Cooking: In most cases beets are cooked separately from what they will eventually be used with. Some swear oven roasting is the only way to go, but I find little difference from boiling, and in sunny Southern California we don't fire up a hot oven if we don't really need to. The skins are easier to rub off if the beets are boiled.