Sunflowers are fairly versatile; height varies, as does soil and lighting preferences. There are many species native to Canada. Provides long summer bloom for the perennial border or cutting garden. Also effective in a native plant or wild garden or as part of a naturalized planting or prairie area.
Botanical Name: Helianthus annuus
Nom Français: Tournesol


Bloom colour: Yellow
Blooms: Fall - Zone 5 | Summer - Zone 5
Pollinators: Butterflies
Sun or Shade: Full Sun
Plant Type: Perennial
Height: Up to 9+ feet (3.5 meters)
North and South America
It grows well in hardiness zones: 3 to 9

Coming from the greek words "helios" (sun) and "ethos" (flower), the sunflower is an exceptional plant with many different attributes. It blooms from mid-summer to early fall. There are quite a variety of different sunflowers, some with branching stems or single stems, some that produce pollen for pollinators and some that don't, small or large varieties, some that produce edible seeds, and so on.


prairies and other grasslands, old fields, roadsides, railroad rights-of-way, savannas, and forest edges
Water requirement: Tolerates drought, but blooms best when watered consistently.
Tolerates a wide range of soils
It is best to sow seeds directly into the soil, after the risk of frost has passed and the soil is at least 10oC. Ensure the roots have enough space to stretch out. When preparing a bed, leave space of about 2 feet down and 3 feet across. Fertilizer or compost is recommended as sunflowers prefer nutrient-rich soils. With larger varieties, it is best to plant them where they are sheltered from strong winds, such as near a fence or a building, as their tops become heavy and wind impact could be devastating.
Smaller varieties are recommended for planting in containers, as they rarely grow larger that a foot. They should be planted 1-1.5 inches deep and 6 inches apart. You can also plant multiple seeds and when the plant is 6 inches tall, thin them out to the strongest flowers.


Easily grown in average, dry to medium, well-drained soil in full sun. Tolerates drought, but does best if regularly watered. Remove spent flowers to extend bloom season.
Bush bean varieties such as wax, lima and green beans; tomatoes, basil, marigolds.
Birds and squirrels will browse the seeds. To avoid this, deter them with barrier devices. If a small moth lays its eggs in the blossoms, simply pick the worms from the plants. Rust and powdery mildew may also affect sunflowers.


Spread: About 1 meter or more
Plant stems may be cut back by 1/3 to 1/2 in late May to reduce overall plant height. Sunflowers dislike having their roots disturbed and transplanting is not recommended. For bouquets, simply cut the stem above any new side blooms in the early morning. They should last about a week in a vase if you change the water daily.


Sunflowers are high in nutrients, including protein and vitamin E, and low in saturated fats. They attract birds, bees and butterflies.
Native to Canada
Slightly acidic to somewhat alkaline soils (pH 6.0-7.5)

Styling and Use

Sunflowers grow best in full sunlight, at least 6-8 hours per day in moist well-draining soils.
prairies and other grasslands, old fields, roadsides, railroad rights-of-way, savannas, and forest edge


Sunflowers are considered heliotropic, which means the flower moves with the sun, from east to west, and then at night back to facing east, again awaiting the morning sun. The tallest ever sunflower recorded was 30 feet and 1 inch tall.


Alongside eating the seeds, Native Americans also used the oils to cure skin ailments. Dyes were also made from the yellow flower and the black seeds. According to many sources, Helianthus annuus is reported to be one of the first crops grown in North America. is supported by its readers and advertisers. If you purchase through a link on this site, the site may earn a commission.

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