Milkweed for late-summer color: 'Cinderella' bears dusty rose flowers that monarchs find irresistible, and it blooms when most perennials are fading. Full sun and ordinary soil are all it needs—once established, it's drought-tough and comes back reliably year after year.

The plant reaches about 2 feet tall and spreads slowly into a substantial clump. Plant in spring or early fall, and don't deadhead the spent flowers if you want seed pods for next season's self-sown seedlings.