Ashy Sunflower
Ohio Prairie Plant Species
Common Name: Ashy Sunflower
Latin Name: Helianthus mollis [Pronounced: ""hee-lee-ANTH-us MOLL-iss"]
Type of Plant: Perennial Forb
Identification Helps: Uncommon sunflower in Ohio, with small 2.5 - 3.0 " flowers, on stems 2.5 - 4.0 ft perennial stems. Stems covered with fine, short hairs. Leaves are heart-shaped, without stems, directly attached to the stems, as shown.
Preferred Growing Conditions in the Wild: Found in both high-quality, little disturbed prairies and also on disturbed prairie sites in Ohio. Requires full sun. Can form large colonies, as this sumflower, like other prairie perennial members of the genus Helianthus, can be allelopathic, which means that the plant excretes chemicals into the soil the restrict the growth of nearby plants.
Preferred Soils: Ashy Sunflower grows in prairies with mesic (normal) to xeric (dry) soils, often in poor soils. Does not grow in hydric (wet) or clay soils.
Seasons of Growth and Bloom: Blooms in August and September.
Natural Distribution in Ohio: Found naturally in modern times in only about 8 Ohio counties, although native ecotypes have been re-seeded in Ohio prairie restorations.
Description and General Information: Ashy Sunflower, sometimes called Downy Sunflower, is one of the most beautiful Ohio prairie plants, although its range in Ohio is greatly reduced from the 19th century. It grows wonderfully in gardens and prairie restorations with proper (mesic, non-clay) soils. Goldfinches and other seed-eating birds flock to the maturing flowers in late September and October.
Each of the Ohio populations are slightly different in morphology. The plants at the NASA Plum Brook Station in Erie County, Ohio's largest population covering several acres, look very different from the same species in the Darby Plains prairie area west of Columbus. Like other native prairie plants, each original population of this species was genetically isolated by Ohio's great forests. Ohio prairies were large grassy islands in a massive sea of forest. Consequently, each large prairie developed unique, local ecotypes. For this reason, it is important that seeds of species like Helianthus mollis not be arbitrarily transferred or mixed with those in other areas. The seeds of Erie County Ashy Sunflowers should be retained in northern, Lake Plain counties, with central Ohio seeds retained there.
For garden or landscape use, however, everyone is encouraged to plant this beautiful wildflower. Except in clay soils, it grows easily.