Mexican Sunflower

Mexican sunflower (Tithonia rotundifolia) is a warm-season annual in the daisy family, native to Mexico and Central America. It grows fast and can reach 2 to 6 feet (61 to 183 cm) tall, with a width of 2 to 3 feet (61 to 91 cm).

Its orange-red flowers, about 3 inches (8 cm) across, bloom from mid-summer to fall and attract bees, butterflies and hummingbirds.

Sowing. Sow seeds outdoors directly in the garden after the last spring frost. Barely cover the seeds, because they need light to germinate. Sow when the soil is 70 to 85 °F (21 to 29 °C); seedlings usually appear in 7 to 14 days.

You can also start seeds indoors 6 to 8 weeks before the average last spring frost for earlier blooms. Plant in full sun. Thin plants to about 2 feet (61 cm) apart. In cool summers, late direct-sown plants may not bloom.

Light and soil. Full sun gives the best growth, and it does well in poor to average, well-drained soil. Rich soil or heavy nitrogen makes more leaves than flowers and weak stems that fall over.

Water. Once established, it tolerates drought.

Support. Stems are brittle, so staking is often needed, and shelter from strong wind helps.

Pinching. Pinch back plants, or shear them by about a third in early summer, for bushier growth. Deadhead spent flowers to keep it blooming.

Few serious pest or disease problems are reported. Slugs and snails may feed on young growth, foliage and flowers, so check for damage. Deer tend to leave it alone because its rough leaves and hairy stems deter them.

For cut flowers, pick blooms when they are 90 to 100 percent open, then stand the stems in deep, warm water for several hours. Seed heads form after the flowers fade; wait until the stem turns brown before cutting off the spiky mass.

Store collected seed in a brown paper bag until planting time the next spring.