If you want a bold, tropical look in a plant that comes back each year, Hibiscus × 'Marshmallow Moon' delivers. Also known as Rose Mallow 'Marshmallow Moon', this hardy hibiscus produces enormous, pure white, dinner-plate flowers during the warmest part of the season, with a long display that runs from midsummer into early fall.
Give it the right site and it becomes an easy centerpiece. Plant it where it can soak up sun (full sun is ideal, though it also handles part shade) and where the soil stays evenly moist. It is a great choice near downspouts, at the edge of a rain garden, or anywhere you can water regularly during hot, dry stretches. A layer of mulch helps keep the root zone cool and reduces moisture swings.
Expect a strong, upright habit that finishes about 36-48 inches tall and can spread 48-60 inches wide at maturity. Space plants so air can move through the foliage and so the big blooms have room to show off. In spring, be patient: hardy hibiscus can be slow to break dormancy, then it quickly pushes vigorous new growth once the weather truly warms.
Care is simple. Water deeply as needed, feed lightly in spring if your soil is lean, and cut stems back after frost or in early spring before new growth begins. The flowers are a nectar stop for hummingbirds and other pollinators, and the plant can also contribute to a butterfly-friendly garden.