- Common Name(s):
- Narrow leaf sunflower, Swamp sunflower
- Annuals, Herbs, Native Plants, Wildflowers
Helianthus angustifolius, commonly called swamp sunflower or Narrow leaf sunflower, is a native annual member of the Asteraceae or sunflower family and is a favorite of gardeners. It has deep green sandpapery, simple narrow leaves and it blooms profusely with happy yellow flowers from late summer to fall. Prune plants back in June for a bushier appearance when it blooms, but overall it is a low maintenance plant. Narrow-leaf sunflowers are salt-tolerant and can tolerate water-logged soil so they are great for coastal gardens. Under ideal conditions, it can become weedy spreading by underground rhizomes. Save seed from your favorite plants to plant next year. Plants grow very rapidly so there is no need to start seeds indoors.
Regions: Mountain, Piedmont, Coastal Plains
Seasons of Interest:
Bloom: Late Summer, July-August Nut/Fruit/Seed: Fall
Wildlife Value: This plant is moderately resistant to damage from deer. It is a great late-nectar plant for butterflies. It is a host plant for the Silvery Checkerspot butterfly. Songbirds, ruffed grouse, quail, mourning doves, and small mammals are attracted to seeds so leave standing dead flowers into the winter as natural bird feeders.
Members of the genus Helianthus support the following specialized bees: Andrena (Callandrena s.l.) accepta, Andrena (Callandrena s.l.) aliciae, Andrena (Callandrena s.l.) helianthi, Melissodes (Eumelissodes) agilis, Dieunomia (Dieunomia) heteropoda, Megachile (Sayapis) pugnata, and Paranthidium (Paranthidium) jugatorium.
Insects Diseases and Other Plant Problems: Caterpillars and beetles often chew on the foliage but seldom cause enough damage to warrant management. Rust, leaf fungal spots and powdery mildew are somewhat common. Because stems can be flimsy, plants may need to be staked, especially if planted in a windy location.
- Late summer, fall
- Full sun to partial shade
- Yellow, red, mahogany, bicolor rays with brown to purple center disk
- 6-10 ft
- 1.5-3 ft
- Flower Color:
- Bright yellow
- The 7 in. leaves of the Swamp sunflower are very narrow, rough, sandpapery, simple, hairy and pointed at the tip. They have hairy stems. It often has untoothed, stalkless cluster of smaller leaves in the axils.
- Swamp sunflower has 2-3 in. flowers with a purplish brown disk and 10-20 petals. Also narrow, pointed, hairy bracts.
- Herbaceous perennial
- Swamp sunflower grows best in sandy woods, wet prairies, thickets, low pinelands, flat woods, moist road shoulders, bogs, swales, ditches. It prefers moist soils and full sun but tolerates poor soils on the dry side.
- full sun, partial shade
- Sunflower seeds
- sandy, salty, water-logged
- mountains, piedmont, coastal plain
- United States
- Life Cycle:
NCCES plant id: 2858