AUBURN UNIVERSITY, Ala. – Sunflowers are highly valued economically, but they seem to be overlooked when choosing plants for landscapes. Few plants can boast better color, yet they are not often seen in flowerbeds like many other plants. Sunflowers make excellent temporary hedges and screens and provide a showy backdrop for flowerbeds, while dwarf cultivars make excellent borders and color beds.
When to Plant Seeds
Plant seeds after any danger of spring frost has passed. The seeds can be either sown directly on the open ground and then lightly raked in, or planted individually in a hole twice as deep as the width of the seed. Germination occurs in 10 to 14 days at temperatures from 65 to 85 F. Most sunflower varieties mature in 85 to 95 days. Sunflowers need full sun and will bloom from late summer until frost.
When to Thin
Thin the seedlings to prevent overcrowding once they reach 8 inches in height. Spacing depends on the variety and the purpose of planting. Sunflowers can grow in the poorest soils and do not require additional fertilization, but a broadcasting handful of a complete fertilizer will encourage stronger growth and more flowering.
“Seeds from backyard sunflowers can easily be harvested,’ said Lucy Edwards, an Alabama Extension regional agent in Home Grounds, Gardens and Home Pests.
Growers should watch for the back of the flower head to turn brown and dry. This is the time to harvest the seeds.
“At this time, most of the petals have fallen off and the seeds will appear plump and white striped. Cut the flower head from the stalk. Rub with your hand to remove seeds,” Edwards said. “Allow it to dry then store in a dry place. To keep birds and squirrels from feeding on the heads prior to harvesting, cover the heads with a paper sack.”
Varieties for Cut Flowers
Several varieties of sunflowers have been introduced especially for cut flowers. The following list was taken from the Shepherd’s Garden Seeds catalog:
- Floristan- has bicolored flowers in reddish-brown petals with yellow tips around a dark brown disc. It grows to a mature height of 3 ½ feet.
- Inca Jewels- ranges in color from bright yellow, banded gold to orange, burgundy and bi-colored bronze. This variety has a high tolerance to heat and drought and grows 5-8 feet tall.
- Sunrich Lemon- has heavy single flowers with lemon yellow petals around a black disc. This variety is pollen-less and grows 4 to 6 feet tall.
- Sunrich Orange- this pollen-less variety has deep golden petals with black discs. It grows 4 to 6 feet tall.
- Italian White- has pale lemon-custard petals with brown centers and grows 5-8 feet tall.
- Music Box- has multi-branched dwarf sunflowers. The 4-inch flowers range in color from yellow to gold to a gold-bronze bi-color. It grows 2.5 feet tall.
- Golden Pheasant- has densely petaled double flowers with multiple flowering on branching stems and grows 4 to 6 feet tall.
- Sunbeam- this variety closely resembles the famous Van Gogh sunflowers and grows to a height of 4 to 6 feet.
- Sundance Kid Dwarf- this variety is the earliest to mature, in just 45-50 days from sowing. The 5-inch flowers come in a variety of petal and disc colors. This variety grows well in containers, beds and borders and reaches 15 to18 inches tall.