Helianthus Species, Mountain Sunflower, Narrow-Leaved Sunflower, Swamp Sunflower

Helianthus angustifolius

Family: Asteraceae (ass-ter-AY-see-ee) (Info)
Genus: Helianthus (hee-lee-AN-thus) (Info)
Species: angustifolius (an-gus-tee-FOH-lee-us) (Info)
Synonym:Discomela angustifolius
Synonym:Helianthus angustifolius var. planifolius
View this plant in a garden



Water Requirements:

Requires consistently moist soil; do not let dry out between waterings

Very high moisture needs; suitable for bogs and water gardens

Sun Exposure:

Full Sun



This plant is resistant to deer

Foliage Color:

Unknown - Tell us


6-8 ft. (1.8-2.4 m)


9-12 in. (22-30 cm)


USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Where to Grow:

Grow outdoors year-round in hardiness zone


Unknown - Tell us

Bloom Color:

Bright Yellow

Bloom Characteristics:

This plant is attractive to bees, butterflies and/or birds

Bloom Size:

Unknown - Tell us

Bloom Time:

Mid Fall

Late Fall/Early Winter

Other details:

May be a noxious weed or invasive

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

Patent Information:


Propagation Methods:

By dividing the rootball

From seed; direct sow outdoors in fall

From seed; direct sow after last frost

Self-sows freely; deadhead if you do not want volunteer seedlings next season

Seed Collecting:

Allow seedheads to dry on plants; remove and collect seeds


This plant is said to grow outdoors in the following regions:

Auburn, Alabama

Birmingham, Alabama

Heber Springs, Arkansas

Knights Landing, California

Sacramento, California

San Jose, California

Santa Rosa, California

Keystone Heights, Florida

Newberry, Florida

Ocklawaha, Florida

Oldsmar, Florida

Riverview, Florida

Tarpon Springs, Florida

Venice, Florida

Augusta, Georgia

Cordele, Georgia

Gainesville, Georgia

Hinesville, Georgia

Hull, Georgia

Lagrange, Georgia

Savannah, Georgia

Winterville, Georgia

Benton, Kentucky

Covington, Louisiana

Greenwood, Louisiana

New Orleans, Louisiana

Thibodaux, Louisiana

Kalkaska, Michigan

Clinton, Mississippi

Florence, Mississippi

Madison, Mississippi

Mathiston, Mississippi

Croton On Hudson, New York

Asheboro, North Carolina

Belmont, North Carolina

Chapel Hill, North Carolina

Selma, North Carolina

Wake Forest, North Carolina

Cincinnati, Ohio

Aloha, Oregon

Oak Hills, Oregon

Columbia, South Carolina

Conway, South Carolina

Newberry, South Carolina

Summerville, South Carolina

Knoxville, Tennessee

Arlington, Texas

Castroville, Texas

Chesapeake, Virginia

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Gardeners' Notes:


On Nov 6, 2018, Engarden from Santa Rosa, CA wrote:

There seem to be several varieties or hybrids of swamp sunflower.
I think the true swamp sunflower has VERY narrow leaves ( ~1/8 inch).
I also have some that have wider leaves (~3/4inch). Some types will have one and only one flower at the end of each stem, others have branching , with
Several flowers. There is even a very pale yellow form ( named " moon- beam") I think. I have to keep them in pots sitting In tubs of water, as I garden in a very dry location. They would never survive in the ground here.
But beware....a lot of perennial sunflower species , Including Jerusalem artichokes will become invasive. Every little piece of root left in the ground will grow a new plant.


On Jul 25, 2013, Fires_in_motion from Vacherie, LA (Zone 9a) wrote:

From one tiny "stick" given to me by a guy at Crosby Arboretum in Oct. 2011, it grew to a massive (8 ft. tall) behemoth clump in under 2 years. I had to tear it out because it looked so ugly and raggedy. What I mean by this is that as each stalk grows to ridiculous heights, they end up collapsing outward since the roots are so tiny (about 8" deep & wide under each 8' stalk). It's a catch-22 because if you water it more, it'll have less of a withered, raggedy look, but it will grow larger and topple outward more. (I planted it in the lowest part of my backyard here in south Louisiana. In other words, paradise for this species.) The plant is covered in tiny sharp hairs that slice your skin up like razors, so wear long sleeves and gloves when tending to it. In fact, wear cheapo cotton g... read more


On Sep 23, 2010, guzelle from Knoxville, TN wrote:

I started with 4 plants given to me by a neighbor 4 years ago and I now have hundreds of stalks of the swamp sunflower. I love them when they're blooming and the bees and birds are stopping by, but man, are they invasive! I do absolutely nothing by the way of caring for them: no extra watering, fertalizing them, nothing except cutting them down in the winter and trying to get rid of the ones that have spread into the yard. And that doesn't work very well. They get the full morning sun, are in open yard, and have lived through drought and super rains. Until I got this month's Southern Living I had no idea even of the name. Found this site and have read all comments, etc. I'd like to know if anyone has them under the eaves of the house where they'd get practically not water. I'm a laz... read more


On Oct 15, 2009, Got2btuf from Heber Springs, AR wrote:

This is a nice late season bloomer that brings color to the fall. My Mother has a single plant that is taller than the eves of her house and is in full bloom this year (2009) in the middle of October. It is facing the south sun and came up voluntarily a couple of years ago. I am posting a picture of it.
Thanks, Barbara


On Oct 16, 2004, IslandJim from Keizer, OR (Zone 8b) wrote:

I know this plant only as a blaze of early autumn color along I-75 in Sarasota County, Florida. It is so spectacular. Today, I finally pulled off the road and photographed it. If anything, it's prettier up close than from the middle lane. It's quite rangy in the wild but I have seen nursery catalogs that offer a dwarf cultivar [apparently developed in New Zealand] with very dense, compact growth behavior, but also with the same relatively short 2-month blooming season.


On Sep 24, 2004, henryr10 from Cincinnati, OH (Zone 6b) wrote:

From the posted Zip Codes I appear to be the farthest North reporting on this plant.
I've had it for at least 6 years so it's hardy to at least -15F.
While may be a bog plant it is also very happy here w/ just regular soil, partial sun and natural watering.
I top-dress w/ manure every Spring and forget about it.

Ours gets about 6-7' tall w/ a spread of about 2 1/2'.
It starts blooming in Late Aug/early Sept and is at it's peak right about the first day of Fall.


On Jan 17, 2003, ButterflyGardnr from Orlando, FL (Zone 9b) wrote:

I planted this against the foundation of the house. Most of the year this plant is a rosette of leaves. In mid- summer it sends up a bloom spike, which can be pruned back until about the end of August or early September to reduce its height. I have not ever trimmed mine. The canes of this plant have grown to about 10-12 feet high in my yard and are blown over fairly easily in the wind. One advantage of this is that the plant produces more blooms along the stems. The yellow blooms are quite showy when planted in mass. The blooms will draw some bees and butterflies, but the bigger draw is the birds who perch on the stems and feed on the relatively large seeds as they ripen. Yellow-throated vireos got a lot of my seeds this year (2002).


On Nov 27, 2001, Floridian from Lutz, FL (Zone 9b) wrote:

This plant is a member of the huge plant family, the Asteraceae (formerly called Compositae). Included in this group are all of the plants that are referred to as "Daisies", and "Sunflowers", among others. This plant can be grown in moist soil and in shallow, slow moving water that is no more than a few inches deep. It will also adapt well to dry roadside areas.

It does get tall with plenty of water but is limited in height in dry areas. One way to control its height and to increase the bloom is to pinch it back as it grows. Stop pruning it when it begins to produce flower buds. In the South it begins to bloom in September or October and continues into December. When it is done blooming, cut it back fairly short. Clumps of plants grow back in the following season. Propagatio... read more


On Oct 15, 2001, Amaryllisgal from High Springs, FL (Zone 8b) wrote:

SOILS: Fairly adaptable. Grows most vigorously in moist soils, but does fine in average garden soils. Drier soils will help keep the plant smaller and more contained.

HEIGHT: From 4 to 8 feet, depending on soils.