Also called Mexican sunflower. Years ago, I planted a wildflower mix, and the planting was soon dominated by 4-foot tall plants with single, reddish-orange flowers. I never was able to figure out what the flower was until I happened upon a similar planting at the Olbrich Gardens in Madison, Wisconsin. It was tithonia. The tall plants have attractive, soft green foliage with a fairly large number of bright 4"-5" blooms. I find this very striking, especially as a backdrop plant to other vivid colored annuals like zinnias and calendula.
Germination: 7-14 days
Germination Temperature: Optimum soil temperatures 70-80ºF
Seed Planting Depth: Sow on the surface, seeds need light to germinate
Starting Indoors: Start indoors 6-8 weeks before the last frost. Provide 70-80ºF soil temperatures until germination. Transplant 12-24” apart after the last frost.
Sowing Outdoors: Direct sow outdoors after the last frost, only in areas with long growing seasons
Growth Habit: Upright, branching
Height and Width: 4-6’ x 2-3’
Spacing: 12-24” apart
Light Needs: Full sun
Soil Needs: Average to poor, dry, well-drained
Approximate days to flower from seed: Blooms in 85-90 days
Uses: Cut flowers, beds and back of borders, cottage gardens, containers and planters, attracts bees, butterflies, and hummingbirds, drought tolerant, deer resistant
Care: Deadhead to encourage more flower production. Over-fertilizing will produce plants with more foliage than flowers. Tall plants can benefit from staking