Dwarf Sunflower

Dwarf sunflowers are short forms of the common sunflower, Helianthus annuus. Sunflower cultivars of 3 feet (90 cm) or less are called dwarf types, and they work well in front of beds and borders, in small spaces, or in containers. The plant is an annual that completes its life cycle, from germination to seed, in one growing season.

The daisy-like flowers attract bees, and the seeds that follow feed finches. Birds are drawn to the seeds, so leaving dead flower heads standing through winter gives them natural bird feeders.

Sow seeds outdoors after the last spring frost, once the danger of frost has passed and the soil is above 50°F (10°C). Sow small groups of 3 to 4 seeds after the last frost. Plant them about ½ inch (1.3 cm) deep; other guides advise about 1 inch (2.5 cm) deep or 1 to 2 inches (2.5 to 5 cm) deep. Keep the soil moist until the seeds germinate.

Seeds germinate in 7 to 14 days when kept at 70 to 75°F (21 to 24°C), or within 1 to 2 weeks. Once true leaves appear, thin to one plant per spot. Taller types should be thinned to stand 2 to 2½ feet (61 to 76 cm) apart and staked against wind, and planted in a sheltered spot to protect them from wind damage.

You can start seeds indoors in biodegradable pots, because seedlings resent transplanting. One option is to sow 1 seed per 6 inch (15 cm) pot about 3 to 4 weeks before planting out. Sources differ on cold tolerance: one says the plant is not frost-tolerant, while another says seedlings can resist mild frosts. Wait until the frost danger has passed before setting plants out.

Give the plant full sun, meaning 6 or more hours of direct sun a day. It does best in well-drained soil with a pH of 6.0 to 7.5.

Water the soil until the seeds germinate. After that, regular watering gives the best flowering and seed production. Feed with a balanced fertilizer such as 10-10-10, and avoid high-nitrogen fertilizers, which promote leaves over flowers.

For pots, choose a dwarf cultivar 3 feet (about 90 cm) or less in height and use a large container, such as a 5-gallon (19 L) bucket with holes drilled in the bottom. Containers dry out faster than garden beds, so they need more frequent watering.

Caterpillars, slugs, snails and beetles may chew the leaves, and the plant can get powdery mildew, leaf spots and rust. Slugs and snails are a common pest of young plants. Birds and squirrels can dig up new seeds and eat seedlings, so netting can protect a new bed. Full sun helps prevent powdery mildew. A fungal disease called Sclerotinia rot can cause brown rot at the base of the flower and wilting plants.

Seed heads are ready when they face downward, the back has turned lemon-yellow, and the inner petals rub off easily. Dry the heads in paper bags or cheesecloth in a dark, dry, well-ventilated place. The petals are edible, and young flower buds can be steamed like artichokes.