How to Grow Annual Sunflowers for Pollinators and Wildlife

As we enter the hot days of summer, many of us are busy making trips to the beach, lighting fires around the old grill, and celebrating our country’s independence. While we try to pack as much into the warmer months as possible, consider planting a plant that symbolizes the climax of the season like no other: the sunflower (Helianthus annualAlthough considered a rather unassuming plant in some circles that is only suitable for novice gardeners, there are many reasons why growing sunflowers can be a boon to your garden. Learn all about how and why to grow sunflowers as annuals below.

Plant sunflowers for pollinators and wildlife

Although many people think of sunflowers as one large flower, the inflorescence or floral structure of Helianthus annuus is actually a compound flower of several flowers. This is a characteristic feature of the Asteraceae family, which includes sunflowers, daisies, chrysanthemums, and others. A compound inflorescence is made up of hundreds, or even thousands, of individual small disc florets within a whorl of ray florets. The outer ray florets are sterile, but the numerous disc florets can all produce viable seeds if properly pollinated. Sunflowers are therefore favored by pollinators due to the high concentration of nectar and pollen provided by thousands of small flowers in a compact space.

Bird enthusiasts among us may consider growing sunflowers to supplement the fall and winter diets of our feathered friends. Sunflower seeds are extremely nutritious, an excellent source of protein and high in calories. As birds prepare for fall migration, sunflower seeds can help them store energy for their long flights. Conversely, winter hardy species enjoy the high fat content of the seeds to keep them warm during the colder months. Goldfinches, great spotted woodpeckers, house sparrows, northern cardinals, black-headed chickadees, juncos, coal doves, crested finches, gray catbirds, white-breasted woodpeckers and many others enjoy sunflower seeds as a food source. Learn more about supporting birds in winter.

To mimic the natural seasonality of migration or winter storage, simply leave the mature flowers on the stem and allow birds and other mammals like squirrels and chipmunks to forage as they see fit. Or, if you want to supplement your food supply throughout the winter, harvest the flower heads when they begin to turn brown and hang them in a dry place for later use. Learn more here.

As well as being a great food source for humans, sunflowers have become a more widely grown agricultural crop. Thousands of acres are planted each year to produce sunflower oil as well as roasted seeds. Roasting your own sunflower seeds can make a delicious, healthy snack or a special handmade gift.

Growing sunflowers from seeds

A relatively quick-to-mature crop, requiring only 85–95 days from planting to harvest. To extend the flowering period, alternate planting seeds or seedlings every 2–3 weeks.

How to sow sunflowers directly:

• As an annual, the simplest way to establish a healthy bed is to sow seeds directly after all danger of frost has passed, sowing each seed 1–2 inches deep and 6 inches apart.
• Depending on the mature size of the cultivar you choose, you may need to thin out the seedlings to avoid overcrowding.
• If planting in rows, leave 2–3 feet between each plant.

How to start sunflower seeds indoors:

• Sowing seeds indoors to encourage earlier flowering after planting outdoors is also a viable option.
• If you are starting your seeds indoors, remember to harden off your seedlings slowly before planting them in the garden. This can be done by placing the seedlings outside for a few hours, preferably in indirect light, and gradually increasing the time outdoors over several days to a week.

What sunflowers need to grow:

• The ideal amount of time is 6 hours of direct sunlight, but they will also like as much sunlight as possible.
• Once the young plant has grown its second set of leaves, I recommend applying a slow release organic fertilizer to aid in rapid growth.

Types of sunflower pests to pay attention to:

• Given the right growing conditions, pests are usually not a major concern. However, deer are quite fond of young, tender plants, so protection with repellents or cages may be necessary if deer populations are high in your neighborhood.

The Best Sunflower Varieties to Try

A wonderful dwarf sunflower variety
‘Teddy bear’ 18-24″ tall with bushy habit Flowers have unique, unusual textures Many flowers on one tree
Sunflowers are best for wildlife
‘Black Oil’ Flowers have yellow petals with a yellowish-brown center that turns black when the seeds are ripe. The seeds contain more oil than most other sunflower seeds. Great food source for birds
An unusual color in sunflowers
‘Black Beauty’ The outer petals are dark red in the middle and lighter red at the tips. The flowers in the middle are black and the leaves are dark green. Multi-flowering/multi-branching habit Long flowering time
For the true sunflower enthusiast
‘Gray Striped Elephant’ The classic giant sunflower, true to its name Can grow up to 12′ tall with flowers 10″ in diameter Large flowers are capable of producing large numbers of seeds.
A sunflower for a paler garden
5. ‘Iced Vanilla’ Up to 5′ tall Flowers 3″–5″ wide, cream, pale yellow Flowers and buds are edible and can be added to summer salads for a pop of color.

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Adam Glas is the garden supervisor and rose grower at the Scott Arboretum at Swarthmore College in Swarthmore, Pennsylvania.