These days the roadsides are littered with bright yellow spots of color. Although they are much smaller than many of the cultivated varieties, these native sunflowers provide color and food for birds, just like their taller counterparts.
Helianthus grosseserratus is the botanical name for these roadside natives known commonly as saw-tooth sunflower. Helianthus is Greek for “sun flower,” and these flowers are so named because they follow the sun when in bloom. Grosseserratus is Latin for “coarsely toothed” or “saw-like.”
Missouri is home to 15 native sunflower species, and they are found across the state. In fact, H. grosseserratus can be difficult to identify because it easily hybridizes with other sunflower species. There are 11 known hybrids of H. grosseserratus
Helianthus are members of the Asteraceae family. They are characterized by yellow flowers of varying sizes. They range in height and size, too, but all sun flowers grow in sun.
H. grosseserratus flowers are about three and half inches in diameter. The flowers have yellow petals with a light brown center.
Ten to 20 flowers will appear in broad ray off the main stem of the plant on H. grosseserratus. Flowers will blossom from July through October.
The leaves of H. grosseserratus are about two and half inches wide and 10 inches long. The narrow leaves have a “toothed” edge.
Like many native flowers, the sawtooth sunflower grows in prairies, meadows and fields and along roadsides. Soil requirements are minimal, but the sunflower will not grow in lowlands that are exceedingly moist. Full sun is also a requirement. In the right environment, H. grosseserratus can reach up to 16 feet in height.
In cultivation in the garden, H. grosseserratus will be wide spreading. The plant may benefit from pruning and deadheading to prevent too much reseeding.
And if it gets too big, it may need to be divided every few years.
In the remaining days of late summer, take the time to enjoy the roadside blossoms of our native sunflowers.
Questions or comments related to gardening? Contact Joleen at firstname.lastname@example.org.