Pronounciation: Gos-SIP-ee-um hark-nes-SEE-ii
USDA 9-11 (best in semi arid to arid zones)
Landscape Use: filler shrub for xeric landscapes, rock gardens, native desert gardens, hummingbird gardens.
Form & Character: Evergreen shrub, gently sprawls, brittle, sometimes sparse
Growth Habit: Slow to moderate growth rate to 5 feet height with greater spread depending on cultivar and soil conditions, watering, fertility, etc.
Foliage/texture: Classic cordate (heart shaped) leaves, alternate, thick and almost succulent with prominent palmate veination much like a miniature Algerian ivy leaf (Hedera canariensis), leaves born on relatively thick and chunky stems with lenticels; medium texture
Flowers & fruits: Bright lemon-yellow petaled, open face flowers, 2 inches in width with five red dots, from late spring to the fall; fruit much like cotton balls. Closely related to Gossypium hirsutum (cotton).
Seasonal color: Subtle yellow blooms during mostly spring.
Temperature: Heat tolerant, cold hardy to 25oF.
Light: Full sun, though avoid highly reflective western exposures as leaves will turn chlorotic yellow.
Soil: Actually prefers poor soils, salt tolerant. Avoid excessive amount amounts of organic matter amendments.
Watering: Responds well to irrigation, but to much watering can cause it to look rank. Too little water though and the foliage looks sparse. So, infrequent and deep irrigations are best, especially during summer months.
Pruning: Head back relatively infrequently.
Disease and pests: None
Additional comments: San Marcos hibiscus is a great but infrequently used spreading shrub for native desert gardens. Don't be dismayed by how poorly this desert native shrub does when growing in a nursery container with an abundance of organic matter substrate. Put it in your desert yard in its favorite desert spot with desert poor soil and it will transform into a very tough and dependable looking native plant.