The Swamp Sunflower, as the name implies, is grown best in wet soil. It is a good addition to a rain garden. It grows up to 6 feet tall and blooms from mid-summer to first frost. This sunflower is an important ecological resource for many pollinators and birds. It is the host plant for butterflies such as the Painted Lady, and is an important nectar source for Monarchs migrating south. The seeds are eaten by birds, helping to sustain them over the winter.