Native Sunflowers of Ontario

~ Sunflowers (Helianthus)and their look-alikes (Heliopsis & Silphiums) ~

Updated Nov 26, 2020

Sunflowers are aptly named plants. Their cheerful yellow flowers are an ode to the summer sun and will light up any garden. However, as ecological gardeners, we know that a plants value should not be based upon looks alone. Sunflowers have a lot of value to bring to wildlife gardens from an ecological and a design standpoint. In this article we will examine the different native sunflowers, and sunflower look-alikes, in Ontario and how to use them in your garden.

Why Your Wildlife Garden Needs Sunflowers

Host plants

Native sunflowers support a wide diversity of pollinating insects

If you want to support butterflies in your garden then it’s important to provide food for their larvae (caterpillars) as well as flowers for the adults. Sunflowers happen to be excellent host plants! Their leaves feed the caterpillars of about 73 different butterflies and moths and many other insect species.

This is not only important it you want to see more butterflies in your yard, but supporting insects means that you are supporting birds. In fact, 97% of birds rely on insects alone to feed their young - not seeds or berries.

Sunflowers (Helianthus) are host plants for caterpillars of the Silvery Checkerspot, Gorgone Checkerspot among others.

Specialist Pollinators

Roughly 25% of native bees in Eastern North America are pollen specialists, meaning they only forage pollen from one or two types of plants, sometimes three. This is a mutually beneficial relationship but can also act as a downfall if the bees’ host plants are not available due to habitat loss.

Sunflowers are recognized for their ability to support specialist pollinators in the genus’ Andrena, Melissodes and Colletes.

Sunflowers also support a wide variety of generalist native bees, butterflies and flies. Often, you can find male native bees spending the night congregated on sunflowers.

Wildlife Habitat

All of the plants listed below have hollow stems. Why are hollow stems important? Well, 30% of our native bees nest in cavities such as hollow stems. Sunflower stems have pithy centers and hard exteriors which creates a perfect opportunity for cavity nesting bees to hollow them out and raise their young in. You can help them out by leaving your plants standing over winter and only cutting back plants in the springtime.

When you do cut back your plants in the spring, leave to at least 1ft standing for this seasons bees to nest in.

Versatility in the garden

Sunflowers are associated with a wide variety of habitat types in Ontario. Oak woodlands, forest edges, prairies, meadows and even wetlands. Therefore, you will find that they are fairly versatile plants with a variety of growing preferences and heights.

Some sunflowers are more picky about where they grow than others, so always do your research and choose the one best adapted to your site/needs.

Native Sunflowers of Ontario

Woodland Sunflower (Helianthus divaricatus)

Giant Sunflower (Helianthus giganteus)

Pale-leaved Sunflower (Helianthus strumosus)

Sunchoke (Helianthus tuberosus)

Sunflower look-alikes:

False Sunflower (Heliopsis helianthoides)

Compass Plant (Silphium laciniatum)

Cup Plant (Silphium perfoliatum)

Prairie Dock (Silphium terebinthinaceum)

Woodland Sunflower (Helianthus divaricatus)

Height: 1.8m, 6ft

Exposure: Sun to part sun

Soil: Sand, loam, clay. Average to dry.

Woodland Sunflower is naturally found in dry, open woods or savanna so, in your garden, it will do best in part sun with average to dry soil. It is a prolific bloomer and has a very sturdy, upright form. It is very adaptable and will grow in full sun and tolerate drought conditions. It will grow in part shade too, but with reduced flowering (I find they tend to flop more in shade).

Woodland Sunflower spreads by rhizomes and self-seeding, although seeding tends to be the primary reproductive method. Control it’s spread by planting in drier soils or planting your garden densely so it doesn’t have room to spread.

It makes an excellent structural plant as it holds its form well into the winter months to provide year-round garden interest. The leaves even provide fall interest by turning shades of yellow.

Some good companions for Woodland Sunflower include Giant Yellow Hyssop, Indian Grass, Switch Grass or New England Aster.

Woodland Sunflower is juglone tolerant meaning you can plant it near Walnut trees. As a bonus, the rough leaves make it deer resistant! It is also a good choice for long-lasting cut flowers.

Giant Sunflower (Helianthus giganteus)

Height: 3m, 10ft

Exposure: Sun to partial shade

Soil: Sand, loam. Moist, well-drained.

Giant Sunflower really earns it’s name by growing up to 10ft tall! Its showy yellow flowers are clustered at the top of tall, unbranched stems. Naturally, it is found in moist prairies, sedge meadows and other wet, sandy areas.

In your garden it will do best in full sun with moist, but well-drained, soils. The tall stature and prolific blooms add a dramatic look to meadow/prairie garden.

Due to it’s height and ability to spread it may not be the best choice for small gardens, however it is an excellent structural plant for larger gardens.

Giant sunflower is Juglone tolerant so you can plant it near Walnut trees. Rough leaves and stems make it deer resistant.

Pair Giant Sunflower with New York Ironweed, Spotted Joe-pye or Cut-leaf Coneflower.

Pale-leaved Sunflower (Helianthus strumosus)

Height: 1.2m, 4ft

Exposure: Sun, part sun

Soil: Sand, loam. Average to dry

Pale-leaved Sunflower brings the sun to that shady corner of your yard! It is naturally found in a diversity of habitats including oak woodlands, prairies and meadows. In your garden, it will in both full sun and dappled shade.

The open-branched stems are topped with clusters of small, yellow flowers that bloom from mid-summer into fall.

Pale-leaved Sunflower spreads from rhizomes and tends to self-seed too. In good conditions it will form small colonies. It maintains it’s structure over winter, giving it full-season interest.

This is one of the shortest native sunflowers in Ontario so it is much easier to get up close to the flowers and observe the pollinators!

Companion plants in a light shade setting include Large-leaf Aster, Bluestem Goldenrod, Pensylvania sedge or Wild Columbine.

Sunchoke (Helianthus tuberosus)

Height: Up to 3m,10ft

Exposure: Sun, part sun

Soil: Sand, loam, clay. Moist to dry.

Known as a'skibwan' by the Anishinaabe, Sunchoke is a very valuable plant that provides food for humans and wildlife alike. The fleshy tubers can be cooked like potatoes and were a staple food source for the First Nations. Showy yellow flowers sit atop tall, sturdy stems.

Sunchoke is very adaptable and a prolific spreader. Because of this, it is often considered a garden thug and is best suited to larger gardens. On the other hand, who can complain about free food? Control it’s spread by eating it!

It’s tall, upright stature makes it a perfect structural plant for the back or middle of a garden. The dead stems will last until heavy snow weights them down. Harvest the tubers after a few hard frosts have hit the plants.

Any plant that provides food for humans and wildlife is a winner in our books. Try planting Sunchokes with another edible native plant, Groundnut (apios americana). The Groundnut is a vine and will grow up the Sunchokes as a trellis. Double food production from one space!

Sunflower look-alikes (Heliopsis and Silphium)

Alright, the following plants are technically not sunflowers (Helianthus spp. and Silphium spp.) however, they are all closely related and look/act very similar.

Heliopsis and Silphiums may not be the host the same diversity of butterfly and moth larvae as sunflower, however, they support many pollinator species including native bees, butterflies and even hummingbirds. Like sunflowers, the seeds of Silphiums are eaten by songbirds such as Goldfinches.

Silphiums are generally indicators of high quality Tallgrass prairie in Ontario. In southern Ontario, Tallgrass prairie was once found in patches from Chatham-Kent to Peterborough. It once covered roughly 1000 km2, but less than 1 percent remains due to habitat destruction. Help restore some of Ontario’s unique prairie ecosystem into your backyard with Silphiums!

False Sunflower (Heliopsis helianthoides)

Height: 1.8m, 6ft

Exposure: Sun, part sun

Soil: Sand, Loam, Clay. Average to dry.

False Sunflower, known as giizisobagoons by the Anishinaabe, is not a true sunflower (Helianthus) but it looks and acts quite similarly. It’s naturally found in prairies, meadows and open woodlands. It’s very adaptable and will grow in a wide variety of conditions in your garden.

False Sunflower is a multi-stemmed plant that is loaded with showy yellow blooms from early-summer into fall. It is usually the earliest sunflower to bloom.

False sunflower is one of the most prolific spreaders on this list. It spreads mainly by seeds so if you plant your garden densely then it won’t be too much of a problem. It is best suited for medium to large sized gardens and especially good for naturalizing. It is a common component of tallgrass prairie seed mixtures.

Feel free to plant False sunflower by Walnut trees because it is juglone tolerant. Suitable companion plants for False Sunflower include New England Aster, Mountain Mint, Big Bluestem or Indian Grass

Compass Plant (Silphium laciniatum)

Height: 3m,10ft

Exposure: Sun, light shade

Soil: Sand, loam. Average to dry

Compass plant is a long-lived plant (up to 100years!) found in prairies and savannas where it thrives in full sun and moist to slightly dry conditions. It gets it’s name from the fact that the leaves orientate in a north-south direction to maximize water use. The deep taproot of Compass plant can extend 15ft into the ground, making it exceptionally drought tolerant!

Compass plant really makes a statement in garden. Plant it in the middle or rear of a garden as a tall, accent plant. Choose it’s location wisely as it’s deep taproot makes it very difficult to transplant. The above ground stalk is sturdy and persists through winter months, thus adding multi-season interest to gardens. The uniquely lobed leaves will add textural interest to your garden.

Big Bluestem grass and prairie Coneflower both make great companion plants for Compass Plant.

The origin of this native plant in Ontario is unclear as it may have been brought into Ontario a long time ago via railroad lines. However, we will never really know for sure.

Cup Plant (Silphium perfoliatum)

Height: 2m, 7ft

Exposure: Sun, light shade

Soil: Sand, loam, clay. Average to dry.

Cup Plant, known as akandamoo by the Anishinaabe, is found naturally in moist prairies and meadows and shorelines. It prefers moist soil but is surprisingly drought tolerant. Cup Plant’s unique leaves form a natural cup around the stem which collects rain water and holds it for a few days after a rainstorm. This attracts insects and birds who drink from the natural cups.

The showy yellow flowers bloom from mid-summer into fall and act as a beacon for butterflies of all types.

Cup Plant is an adaptable plant and prolific spreader by seed, so avoid planting it in smaller landscapes. However, it makes a great vertical statement in larger native plant gardens, especially when planted in groupings. It also provides great cover for wildlife.

The strong, square stems are sturdy and will stay upright into winter months until wind or heavy snow flattens them. The hollow stems make great habitat for cavity nesting native bees. The foliage is eaten by herbivores such as deer.

Cup Plant is juglone tolerant so you can plant it near Walnut trees!

Prairie Dock (Silphium terebinthinaceum)

Height: 3m, 10ft

Exposure: Sun

Soil: Loam, clay. Moist to dry.

Prairie Dock is a stately plant with large, cordate shaped basal leaves and tall, leafless flower stalks. The flower stalks reach for the sky, often 10ft or more, as if they are trying to be seen by pollinators. It is naturally found in prairies and savannas and likes soils that are slightly on the moist side but it does need good drainage. It can tolerate poor soils and drought, so it’s a very low maintenance native plant. The thick taproot can extend 12ft into the soil making it very drought tolerant and hardy.

The large leaves make a dramatic textural statement in gardens, especially around the finer textures of grasses. The flower stalks rise up into the sky to bring in pollinators from far and wide. The thick stems are self-supporting but may flop a little bit in rich soil. Be patient as it is slow to develop but is indestructible when mature. The foliage is eaten by herbivores such as deer.

Prairie Dock is an indicator of high quality prairie and is critically imperiled in the wild in Ontario.