Giant fleece flower (Persicaria polymorpha) is an underused perennial that is a real showstopper in the garden. Quick to establish, within two to three years of planting it sends shoots up 5 feet. In late spring they will start bearing masses of creamy white flowers. Fleece flower continues to bloom profusely all summer, the flowers mellowing to a tawny tan in September. Because the plant is so tall, the blooms provide a real focal point in the garden, especially at a distance, and they rarely flop over. At maturity the plant will increase to a 5-foot-wide clump, so give it some room.
Persicaria polymorpha is a member of the knotweed family, but unlike that invasive thug Japanese knotweed it stays put and only increases its size where it’s planted. It doesn’t reseed either. Drought tolerant and hardy to USDA Zone 3, giant fleece flower prefers moist, fertile soil and requires at least a half day of sun. You can divide the tuberous roots in spring, and divisions should include a portion of the stem. You’ll find that it makes a
great backdrop companion to daylilies, roses, and ornamental grasses.
Giant fleece flower is available at a number of Twin Cities nurseries that specialize in perennials, but you may not find it at a general garden center. It’s worth tracking down however, because you’ll find few plants that require so little care and provide almost shrub-like scale with so much long-blooming splendor all throughout the summer. Once in bloom it’s certain to attract a lot of attention from your garden visitors.