All About Sunflowers: Native Species & Beloved Cultivars

By Tys Theysmeyer, Head of Natural Areas, Royal Botanical Gardens

Few plant species bring a smile to peoples face like sunflowers. The smiles can get bigger, as the financial support of the Ontario Trillium Foundation is assisting RBG with restoring meadow habitat, also restoring many of our native perennial sunflower species.

Sunflowers have deep historic cultural roots bound to our region and are one of Easten North America’s exports to the horticultural and global economy. Almost all of the around 70 sunflower species originate in North America, while hundreds of cultivars from this 1 species have been adopted across the globe for food, oil and ornamental displays.

Types of Sunflowers

Virtually all sunflowers that would immediately come to mind are almost entirely cultivated from a single species native to Eastern North American, the Common Sunflower (Helianthus annus). Within Hendrie Park by the Turner Pavilion Teahouse this year, you can see a cultivar variety closely resembling the original wild species. At the RBG Centre entrance is among the more extreme cultivars, the Grey Stripe Mammoth developed in Russian for oil seed production.

A dozen other cultivars are found in various gardens this year, all are cultivars of the original annual species, a result of 300 years of intensive global effort for showy flowers, and agricultural seed and oil production.  The original wild version of the Common Sunflower is equally valued and cultivated by First Nations, with its origins in beach and floodplains environments were water scours and shifts around sand and gravel during storms.

Traditional and Modern Uses

Sunflower is sometimes referred to as the fourth sister of the First Nations garden, the three sisters being, corn, bean, and squash. Its uses are many but centered on food and oils. The food angle is both the seeds, but also the root tuber of a few perennial species.

Sunchoke (H.tuberosus) also known as Jerusalem Artichoke, and Giant Sunflower (H.giganteus) are the principle two species, having large starchy tubers. Sunchoke is regularly found our local grocery stores, the tubers resembling odd shaped potato’s, however its form of starch is difficult to digest for many people (Inulin).

In my research into sunflowers, I have come to appreciate the culinary value of sunflower oil, and now do much of my cooking substituting locally grown sunflower oil when oil is called for. Horticulturally speaking Tall Sunflower is my favorite species having bright lemon yellow coloured flowers, and I have since realized the food value for the root tuber. This was driven home to me when I attempted to transplant one in my garden, and it took an axe to split the massive tuber.  

Ontario Native Sunflower Species

Our native perennial sunflowers are largely meadow species, some for wetlands, some for dry sand, and even some species for clay. A total of 7 native species currently exists in the RBG’s natural areas, most are rare currently, but increasing with our meadow restoration initiative. The exception is off course Woodland Sunflower, the most common species of the RBG natural areas found in semi open forested areas.

The number of species native to Ontario is difficult to pin down as much of the sunflowers habitat was taken over historically for agricultural purposes, however my review of the broader North American distribution of sunflowers indicates about a dozen perennial species and two annual species likely where present.

Native Sunflower Species found at RBG

• Pale-leaf Sunflower 
• Woodland Sunflower 
• Thinleaf Sunflower 
• Stiff Sunflower 
• Tall Sunflower 
• Maximillian Sunflower 
• Sunchoke 

As our meadow restoration initiative proceeds, the opportunity to reacquaint ourselves with the diversity and cultural uses of sunflowers will be renewed and perhaps will inspire more discussions of local food and culture.

The meadow restoration project is proudly supported by the Ontario Trillium Foundation.