The thimble cactus is a miniature charmer, its finger-sized stems wrapped in lacy white spines that interlace like crochet work. It offsets readily, so one little plant becomes a cluster of thimbles, and in late winter it surprises you with small creamy-yellow flowers.

Give it your sunniest windowsill and a gritty cactus mix, and water sparingly, letting the soil dry out completely between drinks. In winter, water barely at all. The offsets detach easily, so handle the pot rather than the plant when moving it.