Tithonia rotundifolia
Light: Full sun; light afternoon shade can help during Phoenix’s most intense summer heat.
Water: Water deeply, then let the upper few inches of soil dry. Established plants tolerate brief drought, but regular watering supports flowering during Phoenix summers.
Soil: Well-drained soil; tolerates sandy or moderately poor soils. Avoid waterlogged soil and excessive nitrogen fertilizer.
Mature size: Typically 4–6 feet tall and 2–3 feet wide; dwarf cultivars remain about 2–3 feet tall.
Bloom: Late spring or summer through fall, depending on planting time; flowering may slow during extreme heat and continues until frost.
Evergreen / deciduous: Annual; neither evergreen nor a woody deciduous plant. Usually dies after frost or at the end of its growing season.
Growth rate: Fast; often begins flowering about 3–4 months after sowing.