Helianthus angustifolius is an herbaceous perennial for full to part sun. We call it narrow-leaf sunflower, but you’ll sometimes hear it called swamp sunflower also. Be aware however that there are other Helianthus species which are more commonly known as swamp sunflower in our area. They get considerably taller than narrow-leaf sunflower and spread very aggressively.
Narrow-leaf sunflower is native from North and Central Florida to Texas and as far north as Long Island and west to the Ohio River valley. Although it’s inconspicuous most of the year, you cannot miss its brilliant, yellow flowers in the fall. They would brighten the gloomiest of days; and it’s not stingy with them either. Plant this native perennial in your garden and you will have lots and lots of flowers to brighten your yard with plenty left over to cut and share. Every year Donna Legare (co-owner of the nursery) brings bouquets into the nursery and to friends and neighbors who are under the weather or need cheering up. It always seems like she has a never ending supply. Donna did tell me however to mention that this plant is not for everyone. Like swamp sunflower, it does spread; but we’ll get to that.
If you do decide that narrow-leaf sunflower is for you, give it plenty of room in full sun if possible. If a spot in partial sun is the best you have to offer it, pinch the plants once or twice early in the summer to encourage branching. Otherwise they will probably be leggy. They will still bloom beautifully in partial sun, just not quite as much so as in full sun.
Narrow-leaf sunflower grows to five feet. It attracts butterflies, birds and lots of native bees. It is salt tolerant and pretty pest resistant if it gets enough sun. It also tolerates a wide variety of soils from sand to poorly drained clay soils. It prefers moist soils but thrives in well-drained soil as long as it is watered adequately enough to become established and during dry spells.
Okay, so here’s the warning . . . this wonderful native perennial that is so tolerant of poor soil does spread and will go a little crazy when planted in well-drained, good garden soil. Although it is not as aggressive as swamp sunflower, it will spread by underground rhizomes, and you will find yourself having to pull some up (Donna says they’re easy to pull). For most of us it is well worth the trouble. In my fifteen years here at Native Nurseries, I’ve had more than one customer complain to me about its aggressiveness; but I do not remember any of them saying they were willing to dig it up and get rid of it. Once you’ve experienced this autumn wonder, it’s a hard habit to break.
At Native Nurseries, we typically stock Helianthus angustifolius (a/k/a narrow-leaf sunflower) in quarts and 1-gallon pots. Currently we have 1-gallon pots only. As always, give us a call to check availability before making a special trip (although we’re always happy to see you). Sorry . . . we do not ship plants.
Some information for this blog post came from the following sources –
http://florida.plantatlas.usf.edu/Plant.aspx?id=3497
http://plants.usda.gov/core/profile?symbol=HEAN2
http://www.clemson.edu/cafls/demo/plant_profiles/helianthus_angustifolius%20.html
NC Cooperative Extension
Post Date: 6/11/15