Tropical
Tropical Hibiscus
Hibiscus rosa-sinensis · Malvaceae
Also called: Chinese Hibiscus, Hawaiian Hibiscus, China Rose
Tropical Hibiscus (Hibiscus rosa-sinensis) is a high-water tropical well suited to Tucson and the low desert. It thrives in full sun in winter/spring, with a moderate growth rate.
Tropical Hibiscus at a glance
- Water use
- High (established)
- Sun
- Full sun in winter/spring; in Tucson it benefits from afternoon shade or filtered light in summer to prevent leaf scorch and bud drop. Often grown in movable pots.
- Mature size
- About 4-8 ft tall and 3-6 ft wide in ground; smaller in containers
- Growth rate
- Moderate
- Bloom
- Red, pink, orange, yellow, white, and bicolors depending on variety, Late spring through fall (warm months); blooms cease in cold weather.
- Cold hardiness
- Very frost-sensitive; damaged below ~40F and killed by hard frost. In Tucson needs frost protection or should be brought into a protected microclimate over winter.
- Soil
- Rich, well-drained soil amended with organic matter; dislikes heavy alkaline native soil. Prefers slightly acidic conditions, so iron chelate may be needed to correct chlorosis.
- Native range
- Tropical Asia (China/tropical Pacific; exact wild origin uncertain)
- Best used as
- Accent/specimen, Container/patio plant, Tropical-look color, Poolside planting (in microclimate)
- Wildlife
- Flowers attract hummingbirds, butterflies, and bees.
- Toxicity
- Generally non-toxic / low toxicity to dogs, cats, and humans (ASPCA lists H. rosa-sinensis as non-toxic), though large quantities may cause mild GI upset in some animals.
How to grow Tropical Hibiscus in Tucson & the low desert
Watering
Keep consistently moist, never soggy; in summer heat container plants may need daily watering. Mulch to conserve moisture and protect roots.
Fertilizer & nutrients
Heavy feeder during the growing season. Apply a hibiscus/bloom fertilizer (moderate nitrogen, lower phosphorus, higher potassium) every few weeks spring through fall; supplement iron to counter alkaline-soil chlorosis.
Pruning & care
Prune to shape in early spring after frost danger passes; pinch tips for bushiness and more blooms. Remove frost-damaged wood once new growth appears.
Notes
Not well adapted to the low desert; treat as a high-maintenance tropical accent. Best in a protected, part-shade microclimate or in pots moved to shelter in winter and out of intense summer sun.
Sources: University of Arizona Cooperative Extension; ASPCA Toxic and Non-Toxic Plant List; Pima County Master Gardeners