Many perennials bloom in early or midsummer. If you’re lucky, the foliage that’s left after they finish blooming is attractive. But sadly, sometimes it just doesn’t look all that great.
Let’s consider trumpet lilies (Lilium hybrids). Their big, bright flowers are gorgeous. But when they’re done blooming and you’ve deadheaded them, those stumpy stalks look terrible, and you can’t cut them back because the plants need the leaves to manufacture food for the rest of the season. So plant something in front of them. But choose carefully: The key to a successful pairing is to choose a coverup plant to go in front that has a similar habit and foliage to the spent plant.
Mexican bush sage (Salvia leucantha), with upright stalks and slender leaves, would never be mistaken for a lily, but, as you see at right, the leaf shape and texture are similar enough that the lilies seem to disappear behind it. In this case, because Mexican bush sage is a fast-growing annual, I like to tip it a little bit away from the lilies to give them some breathing room. But if you’re pairing two perennials, watch the spacing. You want them to be close enough for the coverup to work, so it’s OK if they billow into each other. But you don’t want one crowding the other out of the garden!