Narrowleaf Sunflower

Herbaceous

Narrowleaf Sunflower

Helianthus angustifolius

Also known as: Swamp sunflower

Herbaceous Asteraceae EdiblePollinatorWildlife AttractorErosion Control
Hardiness Zone
5-9
Ideal Temp
60–92°F
Survives Down To
-15°F
Life Cycle
Perennial

Narrowleaf sunflower (Helianthus angustifolius) is a perennial sunflower of moist meadows, pond margins, and roadsides across much of the eastern and south-central United States. Tall stems carry numerous bright yellow daisies very late in the season when many other forbs have quit. It brings vertical drama to rain gardens and pollinator hedges without the annual replanting bill of crop sunflowers. ☀️💧 Sun and Water Requirements: - Full sun for strong stems; shade causes flopping. - Moisture-loving; tolerates seasonal wet feet, still needs drainage over weeks, not permanent stagnation. - Rich loam to clay-loam suits it; mulch helps in sandy sites that dry between storms. ✂️ Propagation: - Division of root clumps in early spring before growth surges. - Seeds: cold stratify; sow in trays and transplant after frost. - Cuttings from soft tips possible but division is surer. 🌾 Harvest / Best Use Timing: - Seeds are small but edible to humans and valuable to finches—leave heads standing into winter. - Cut flowers for bouquets at first full color change; vase life is modest but color is loud. - Chop dead stems in late winter to leave hollow stalks for insects one more season.

Good Neighbors
  • Marsh Mallow — shares wet edge habitat with complementary flower form and timing
  • Mountain Mint — insectary companion blooming alongside or just after peak sunflower waves
  • Saltmarsh Aster — where salinity is not extreme, extends autumn composite show in wet ground
Known Threats — Organic Solutions Only
Aphids
Aphidoidea
Banded Winged Whitefly
Trialeurodes abutiloneus
Greenhouse Whitefly
Trialeurodes vaporariorum
Japanese Beetles
Popillia japonica
Lettuce Aphid
Nasonovia ribisnigri
Lubber Grasshopper
Romalea microptera
Root Aphid
Pemphigus spp.
Sunflower Moth
Homoeosoma electellum