Helianthus mollis
ashy sunflower
Overview
Helianthus mollis is a rhizomatous herbaceous perennial growing 2-4 feet (60-120 cm) tall, spreading into colonies by underground stems. The whole plant is covered in soft white hairs that give it a grey-green, ashy look. The leaves are ovate to lance-shaped, 2-5 inches (5-13 cm) long, opposite, stalkless, and clasp the stem at the base. From July to September the stems bear yellow flower heads 2-3.5 inches (5-9 cm) across, each with 15 to 35 ray florets around a yellow central disk. Helianthus mollis grows in dry prairies, glades, roadsides, and open ground across the central and eastern United States. It tolerates drought, heat, and poor soil once established but spreads by rhizomes and can form large patches. The flowers draw bees and butterflies, and the seeds feed birds in autumn. Plants reach full size in 2 to 3 years and may lean in rich soil, where stems grow tall. It spreads less and stands more upright in lean, dry ground.
Native Range
Helianthus mollis is native to the central and eastern United States, from the Great Plains east to the Atlantic states and south to Texas and the Gulf. It grows in dry prairies, glades, roadsides, and open disturbed ground.Suggested Uses
Helianthus mollis is used in prairie restorations, native plant gardens, and dry meadow plantings, spaced 18-24 inches (45-60 cm) apart. Its spreading habit suits large naturalized areas rather than small borders. The late flowers and seeds support pollinators and birds.How to Identify
Appearance
Size & Dimensions
Height2' - 4'
Width/Spread2' - 3'
Bloom Information
Detailed Descriptions
Foliage Description
grey-greenGrowing Conditions
Sun Requirements
Requires 6-10 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Helianthus mollis grows in full sun and dry to medium, well-drained soil, including poor, sandy, and rocky ground. It tolerates drought, heat, and low fertility once established. Water is needed only during extended dry spells in the first season. The plant spreads by rhizomes and can form wide colonies, so it is given room or contained where spread is unwanted. Rich soil and shade produce tall, leaning stems. No fertilizer is needed in average to lean soils.Pruning
Stems are cut to the ground in late winter before new growth begins. Cutting plants back by one-third in early summer lowers height and reduces leaning. Spent flower heads are left for birds or removed to limit self-seeding.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
winter