Looking for a tall yellow perennial flower with a long bloom time? Want it to bring in all sorts of pollinators? Would it be ok if it hosts a large number of caterpillars? Ok – Sawtooth Sunflower has got you covered. I’ve had this plant in my garden for several years and will share all that I’ve learned with you!
In this article:
- What is Sawtooth Sunflower
- What are the benefits of Sawtooth Sunflower
- Identification / Characteristics
- How to grow and care for Sawtooth Sunflower
- What Wildlife, Pests, and Diseases effect Sawtooth Sunflower
- Where to buy Sawtooth Sunflower
- Uses of Sawtooth Sunflower
- Final thoughts
What is Sawtooth Sunflower
Sawtooth Sunflower is a herbaceous perennial flower native to Central North America. Scientifically known as Helianthus gorsseserratus, it will grow 3-12’ tall in full sun and well draining soil. Blooming yellow daisy-like flowers for 4-8 weeks in Summer, it attracts a large number of pollinators and birds.
This is one of the tallest plants I grow, easily exceeding 8′ when plenty of water is available. It stands tall as a sentry at the back of our micro-prairie / wildflower meadow providing a beautiful backdrop. One feature of this plant that I really enjoy is how much the flowerheads will sway under windy conditions. Another nice thing is that even though my plants only get sun from primarily the South and East, they seem to stand tall and don’t lean. Although I have heard from others who had them knocked down by high winds.
I’ve got to tell you something interesting about my experience with this flower. First, I never planted it! It naturally showed up in my backyard micro-prairie. And, I was having trouble identifying it. I even when to plant identification groups with pictures asking for advice. But everyone kept suggesting various members of the Helianthus genus…and I didn’t think any of them were correct.
I was almost resigned to just assuming I had some strange sunflower hybrid until I started looking to perennial sunflowers that were native to other parts of the country. That, plus when I noticed the leaves were opposite in the lower portion, and alternate in the upper half of the plant. That is the real secret to identifying this plant!
Native Range of Sawtooth Sunflower
The primary native range of Sawtooth Sunflower the Midwestern United States, from Minnesota to Oklahoma, and Ohio. Other native populations exist in the Dakotas, Texas, Quebec and Ontario Canada.
Sawtooth Sunflower is highly adaptable though, and has established itself outside of it’s native range. It is adventive in New England, the Mid-Atlantic, and the Louisiana/Mississippi/Alabama. It has even spread to Europe, establishing itself in Lithuania. 
And although I live in Southern Pennsylvania, it has obviously established itself there either via birds or cultivation. As my first plants just ‘showed up’ in my wildflower meadow, and it took me a very long time to identify them, as I was only looking at Helianthus that was native to my area. Once I realized it could be from a different area, and noticed the changing leaf arrangement (opposite==>alternate), I quickly identified it as Sawtooth Sunflower, Helianthus grosseserratus.
Sawtooth Sunflower Reference Table
|Scientific Name||Helianthus grosseserratus|
|Common Name(s)||Sawtooth Sunflower, Sunflower|
|Native Range, USDA Zone||Central North America, USDA Hardiness Zones 2-9|
|Bloom Time||Summer / Fall|
|Bloom Duration, Color||4-8 weeks, Yellow|
|Height||3-15′ tall (1-5 m)|
|Spacing / Spread||3′ (1m)|
|Light Requirements||Full Sun to partial shade|
|Soil Types||Sandy loam to clay loam|
|Moisture||Moist, well drained|
|Fauna Associations / Larval Hosts||Bees, butterflies. / Hosts several butterflies and moths|
What are the Benefits of Sawtooth Sunflower
Sawtooth Sunflower can make and amazing focal point in a flower bed to the back (North side). Seeing the clusters of bright yellow blooms swaying in the breeze on Summer days is as relaxing as it is beautiful.
Initially you will get a super-bloom for roughly one month. This will be followed by sporadic blooms for the next 3-4 weeks. And although not as showy, still valuable to the wildlife they serve.
With a bloom time greater than one month, this will provide you with vivid yellow color for a long period of time. Contrast this with the all-too-common ‘Mammoth’ Sunflowers, who have but a single bloom that lasts at best two weeks.
Sawtooth Sunflower attracts numerous pollinators for the nectar and pollen. But it also has numerous other insect larvae that feed on the plant. Furthermore, lots of birds and rodents enjoy the seeds in Autumn. This flower does a great job of attracting wildlife to your yard.
Identification and Characteristics of Sawtooth Sunflower
Members of the Helianthus genus can sometimes be difficult to identify. This is primarily due to so many of them sharing similar traits. But check the leaves, and in particular the arrangement to better identify this species.
Reaching heights up to 12’ tall, which is impressive for any herbaceous plant, Sawtooth Sunflower does so with a strong central stem. It is reddish-brown or reddish-purple in color, round and smooth. There may be some branching near the very top where the flowers occur.
The leaves of Sawtooth Sunflower are interesting, and the most important attribute to examine for successful identification. In the lower half of the plant they are arranged opposite, but in the upper half they are alternating along the stalk. So, one of most common traits to look for to identify a flower is how leaves are arranged….and it changes depending on where you look on this plant. But in this case, it is almost like the secret decoder ring for identification!
They are quite large at 8” long by roughly 2-3” wide, lanceolate or lanceolate-oblong in shape, with serrated margins (sometimes barely serrated). They will be dark green on the upper surface and a pale white-green underneath. 
Single or clusters of flowerheads will be at the top of the central stem. Each individual flowerhead is 2-4” diameter with 10-20 ray flowers that resemble petals that are bright yellow in color and oblong in shape. There will be overlapping bracts on the backside of the flowerhead that are green and lanceolate or linear-lanceolate.
As an interesting side note, the ray flowers (petals) of Sawtooth Sunflower are only there to attract pollinators, and do not set seed. This is different from other members of the Helianthus genus and Asteraceae family (Echinacea ray flowers set seed, for example).
The root system of Sawtooth Sunflower is fibrous and will produce clump-forming rhizomes. I’ve seen other references state that it may produce clones, similar to some other perennial sunflower species, but I have not experienced that in 3-4 years of growing this plant. It seems to only spread by seed for me.
How to Grow Sawtooth Sunflower from Seed
Like other perennial Sunflowers, Saw-tooth Sunflower seeds need to experience a cold-moist stratification period before they are able to germinate. Specifically, Saw-tooth Sunflower needs 30 days cold stratification, or should be Winter Sown.
This mimics what happens in nature, in that the seed naturally falls from the plant in Autumn, and sits in cold-moist soil all Winter. This process will break the seeds dormancy, allowing it to germinate in the Spring.
If it is Spring and you are interested in starting this plant from seed, you can accomplish the stratification requirements using a moist paper towel and the refrigerator. We have a detailed guide on cold-stratifying using the refrigerator here.
Otherwise, the easiest way to start Saw-tooth Sunflower seeds is by Winter Sowing. This is where you plant the seeds in a special DIY container in the Fall/Winter, and you let mother nature do the cold-moist stratification for you. Come Spring, the seeds germinate when temperatures warm up, and get a big growth boost from the greenhouse effect.
We have a detailed guide on Winter Sowing here. And it is by far my preferred method for starting seeds.
How to plant Sawtooth Sunflower seeds
The planting depth of Sawtooth Sunflower seeds in a container is 1/8″-1/4″ (3-6 mm). This may seem shallow, but it is perfectly fine. Most species of seed that are exposed to cold-moist soil will germinate after the required stratification time. The reason for planting them is often just to better protect them from birds/rodents.
- Fill a suitable container with moist potting soil. Leave a 1/2″-3/4″ gap (6-9mm) from the top of the container. The potting soil should be wet enough that when you squeeze a handful only a few drops of water fall out.
- Gently tamp the soil firm
- Place 3-5 seeds on the soil surface. Press them so they have good contact.
- Cover seeds with 1/8″-1/4″ of moist potting soil.
- Place the container in a location that receives morning sun and afternoon shade.
- Keep the soil moist, watering as needed.
- Once germination occurs, grow the seedlings until they have 2-3 sets of true leaves.
A couple other notes on caring for young seedlings. First, keeping the container in morning sun/afternoon shade is really beneficial. It allows the seedling sunlight for photosynthesis, but protects it from the hot afternoon sun, which can easily dry out small containers.
Second, there is a fungal disease commonly known as ‘damp-off’ disease. It damages the stalk at the interface with the soil, and causes the seedlings to ‘flop’ over and is often fatal.  Excessive moisture at this interface of stalk/soil is the primary cause of damp-off disease.
A frequent situation that causes damp-off disease is when you water at night, when this excess moisture just sits there until the next day. If you keep your plants in morning sun, and water in the morning, then the morning sun will evaporate any excess moisture thereby preventing damp-off disease.
I have direct experience with this disease, and ironically enough I lost a number of sunflower seedlings because of it. I was keeping them on our back porch, which received late afternoon sun. By sunset, the containers would be dry, and I would water them. Sure enough, after a week or two the tiny seedlings began flopping over, and I was staking them with toothpicks! Then I learned about why this was occurring, and switched where I grew my seedlings….
Establishing Sawtooth Sunflower
First year plants will most likely not flower. But, they need care nonetheless. They can be transplanted to their final location once they have 2-3 sets of true leaves. To do this, simply dig a hole that is 2-3 times larger than their current container. Then, sprinkle a handful of compost in the hole and fill the hole with water. Wait for the water to drain, then repeat. Finally, plant your seedling and backfill. Water one more time, and you are finished.
These small first year seedlings are at great risk from being eaten by deer and rabbits (I’ve had deer eat the top half of mature plants). So you really should protect them with Liquid Fence or a cage of some sort.
You can expect flowers in the second year of Sawtooth Sunflower’s life when grown from seed. By year 2-3, it should be putting up several stalks with multiple flowers.
Grow and Care for Sawtooth Sunflower
Sawtooth Sunflower will grow best and be the showiest in proportion to the amount of sun it receives. Full sun is best (six hours per day minimum), but it can grow in partial shade too. In partial shade the plant may only get 3-5′ tall.
For soil, it will grow best in loam with organic matter. But it can grow in sandy loam or clay loam as well.
When it comes to moisture, Sawtooth Sunflower will do best in moist soil to medium moist soil. It can tolerate drought, but this will stress the plant and possibly hinder it’s height or flowers.
For maintenance, Sawtooth Sunflower can be cut back in late Spring once insects have emerged. You should leave at least 12″ of the stalk vertical though, as bees will often come drill holes in the tops of them and lay eggs.
In formal flowerbeds volunteer plants may develop from seed or rhizome. My experience has only been that of self-seeding though.
Sawtooth sunflower will not require any special fertilizer. It should be self-sufficient even in poor soils.
Wildlife, Pests, and Diseases associated with Sawtooth Sunflower
For pollinators, Sawtooth Sunflower will attract a wide variety. Charles Robertson in his exhasutive and amazing 1929 survey observed 72 different species visiting Sawtooth Sunflower. These include 29 species of long-tongued bees such as bumblebees, leafcutters, and mason bees. Also 9 species of short-tongue bees, and 13 different butterfly species.
Furthermore, there are a number of butterfly and moth caterpillars that are hosted by Helianthus grosseserratus.
Like other members of the Helianthus genus, Sawtooth Sunflower will attract a variety of birds. In particular Goldfinches love to eat the seeds. Now, the stalks of Sawtooth Sunflower are weak enough and tall enough that when a finch lands on the seed head they will really make the plant sway.
It is very fun to see it happen, when all of a sudden on a calm day one of your flowers dips or bends a foot or two.
Deer and Rabbits
Deer and rabbits will absolutely browse/eat Sawtooth Sunflower. I’ve seen the damage myself when deer have completely eaten the top half of the plant before it blooms. These plants should be protected by Liquid Fence. During their first year you may wish to cage them to keep rabbits away.
Sawtooth Sunflower is generally disease free. Although it is possible to get certain fungal pathogens such as rust . The effects of fungi is generally cosmetic only and not fatal to the plant. Planting with good airflow and space can reduce the chances of fungus.
Where you can buy Sawtooth Sunflower
Sawtooth Sunflower is not typically sold in nurseries, as it isn’t a typical ‘garden friendly’ plant. But it can be purchased at specialty nurseries that deal in Native Plants. You can find native plant nurseries near you on our interactive map.
Where to buy seeds
We have ordered a variety of native flower seeds from Everwilde Farms, which you can order right from Amazon through our link on our RECOMMENDED PRODUCTS PAGE. (We may earn a small commission when you purchase through our links, at no cost to you. This helps support our website.)
Uses of Sawtooth Sunflower
Sawtooth Sunflower is a huge plant, but it can be easily utilized as a central focal point of a formal flower bed, or along the back edge. It would be wise to give it sun from all sides. My plants only get sun from South and East, and do not lean, but that may not be the case for you as the Helianthus genus is notorious for hybridizing!
And please note that in high-quality soils this plant may become aggressive, and can self-seed. So you should consider pulling new plants an annual Spring chore.
Additionally Sawtooth Sunflower can be a great addition to wildflower meadows, micro-prairies, or as a tall border garden. They make a magnificent sight.
For companion plants, Sawtooth Sunflower grows well with other tall flowers, or medium (3-5′) flowers and grasses. Some suggestions for pairing with other very tall plants would be the following:
- Tall Sunflower (Helianthus giganteus)
- Annual Sunflower (Helianthus annus)
- Maximillian Sunflower (Helianthus maximiliani)
- Cup Plant
- Compass Plant
- New York Ironweed
- Joe Pye Weed
- Big Bluestem grass
Medium sized plants that would grow well with Sawtooth Sunflower
- Beebalm (Monarda didyma)
- Blue Vervain (Verbena hastata)
- False Sunflower (Heliopsis helianthoides)
- Halberd-leaf Rose Mallow (Hibiscus laevis)
- Blazing Star (Liatris spicata)
- New England Aster
- Purple Coneflower (Echinacea purpurea)
- Sneezeweed (Helenium autumnale)
- Wild Bergamot (Monarda fistulosa)
- Tall St. Johns Wort
Sawtooth Sunflower is one of those native plants that is the ‘total package’. It is strong, beautiful, attracts huge numbers of pollinators, hosts caterpillars, and attracts birds. What more could you ask for? I love this flower and look forward to it blooming each Summer.
 – Helianthus grosseserratus. USDA NRCS. Accessed 20MAY2023.
 – Sawtooth Sunflower. Illinois Department of Natural Resources. 2020. Accessed 21MAY2023.
 – Larson, Gary, Aquatic and wetland vascular plants of the northern Great Plains, Fort Collins, Colo. : United States Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station, 1993, pp680.
 – Spencer, Edwin Rollin, All About Weeds, New York : Dover Publications, 1974, p.352
 – Gudžinskas, Zigmantas, and Lukas Petrulaitis. “Helianthus grosseserratus, a new alien plant species in Lithuania.” BOtanica lithuanica 20.2 (2014): 173-176.
 – Stuessy, Tod F., David M. Spooner, and Kayleen A. Evans. “Adaptive significance of ray corollas in Helianthus grosseserratus (Compositae).” American Midland Naturalist (1986): 191-197.
 – Roth, Sally, Attracting birds to your backyard : 536 ways to turn your yard and garden into a haven for your favorite birds, Emmaus, Pa. : Rodale Press, 1998, pp.309
 – James, R.L. 2012. Damping-off. In: Cram, M.; Frank, M.S.; Mallams, K., eds. Forest Nursery Pests. Washington, DC: U.S.
Department of Agriculture, Forest Service: 115–116.
 – Robertson, Charles. “Flowers and insects; lists of visitors of four hundred and fifty-three flowers.” (1928).
 – Lord, Simone. Butterfly Plant Networks in Iowa Prairie Restorations. Diss. Iowa State University, 2022.
 – Hippee, Alaine C., et al. “Host shifting and host sharing in a genus of specialist flies diversifying alongside their sunflower hosts.” Journal of evolutionary biology 34.2 (2021): 364-379.
 – Bess, James, and O. T. I. S. Enterprises. “Conservation Assessment for The Swamp Metalmark (Calephelis mutica McAlpine).” ER USDA Forest Service., editor (2005).
 – Britten, Hugh B., et al. “Effects of host-plant distribution on genetic structuring of two tortoise beetles (Coleoptera: Chrysomelidae: Cassidinae) in the northern great plains.” Annals of the Entomological Society of America 96.6 (2003): 856-864.
 – Anderson, H. W., and P. J. Anderson. “Host Index.” Proceedings of the Indiana Academy of Science. Vol. 29. 1919.
 – Helianthus grosseserratus. North American Ethnobotany Database. Accessed 28MAY2023.
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