Sunflowers: The Happy Plant
By Nancy Hawkins
UCCE Master Gardener
Are you looking for a plant that makes you smile and feel like dancing? How about one that is bright and colorful in our hot summer gardens? Look no further than sunflowers, the happy plant!
Sunflowers thrive in our summer weather and flower in the heat. They can grow to be over your head with big or small flower heads in a variety of colors, or as shorter, bushier plants with colorful heads. All of them attract birds and bees. They can be grown in forest-like clumps, in rows to make summer screens, as features in cottage gardens, or for cut flowers.
Contemporary sunflowers trace their ancestry to plants found at archaeological sites dating from 3000 BC. While they grew abundantly on the Great Plains, sunflowers were first purposely cultivated by Native Americans in the Southwest as a source of medicine, fiber, seeds, and oil. When the European settlers arrived, they immediately recognized the value of sunflowers and sent seeds back to Europe. There they found a place in English cottage gardens and even Van Gogh’s paintings. However, it was in Russia that the sunflower became a major agricultural crop. In the 1960s, the U.S. began sustained commercial production of specific cultivators to produce vegetable oil and seeds.
Growing sunflowers is easy. Sow seeds directly into the soil after all danger of frost has past and the soil temperature reaches 55° to 60°F. You can plant them in rows, in groups or simply scattered about. Place seeds about 6 inches apart in holes 1 to 2 inches deep. Cover and keep watered until seeds sprout in 7 to 10 days. Thin young plants if they look too crowded. Depending on the variety, sunflowers will mature and develop seeds in 80 to 120 days. Sow more seeds every 2 to 3 weeks to enjoy continuous blooms into the fall.
As their name suggests, plant all varieties in full sun, although some late afternoon shade is fine in our area. Some of the taller varieties might need to be staked to keep them upright. Beware of snails and slugs when they are still young plants. Other than that, sunflowers are delightfully uncomplaining.
Sunflower roots spread widely and can withstand some drought. Deep, regular watering helps encourage root growth, which is especially helpful with taller varieties bearing top-heavy blooms. Sunflowers do not require fertilizer. However, you can add a slow-acting granular fertilizer to especially poor soil. The better their diet, the larger the flowers. Spreading a 2- or 3-inch organic mulch layer on the soil will reduce moisture loss and discourage weeds. They are so easy to grow they often reseed themselves, springing up beneath a bird feeder or where they were planted the previous year.
Birds can be a problem when seeds ripen and harvest time approaches. If you do not plan to use the seeds, it is fun to watch wildlife enjoy the bounty. I even cut the flower heads off and lay them out in the sun to dry to provide easier access to wildlife. On the other hand, to deter birds, cover the seed heads and flowers with a white garden cloth. Also, try cutting away the few leaves closest to the heads to make it harder for birds to perch and feed.
Annual sunflowers must be planted (or started from small plants) each year. There is a wide range of color and bloom size among annual varieties. They are readily available as seeds in local nurseries, big box stores, or from seed catalogues.
Two popular tall growing annual varieties are: Heliantus ‘Moonwalker’, grown for its yellow face with a chocolate dark center growing to 4 to 5 ft. H. ‘Russian Giant’ is the one to get if you want to be in the record books. It is capable of getting 10 feet high with a huge face of yellow petals surrounding the dark center. Spectacular! There are smaller varieties that can be grown in containers or at the front of a border. Look for H. ‘Big Smile’, an aptly named midget that won’t grow above one foot high; or H. ‘Teddy Bear’, producing downy, double blooms on short stems, up to two feet high.
Good companion plants for sunflowers in the summer garden are tall ornamental grasses, such as Miscanthus or Calamagrostis. Water-wise plants such as Salvias, Nandinas, and Agastache also blend in nicely. So, sing and dance away as you enjoy sunflowers in your garden.
The UCCE Master Gardeners will be available to answer your gardening questions at the Tulare Garden Festival on April 6 from 10 a.m. to 2 p.m. at Tulare Public Library, 475 N. M St. in Tulare; each Friday at the Visalia Senior Garden, 310 N. Locust St. from 11 a.m. to noon; and each Saturday at the Visalia Farmer’s Market in the Sears parking lot from 8 to 11 a.m.