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Scientific: Asclepias curassavica
Common: tropical milkweed, blood flower, Mexican butterflyweed, scarlet milkweed, matal, hierba de la cucaracha
Family: Asclepiadaceae
Origin: Tropical regions of North and South America, broadly naturalized globally across tropical and sub-tropical regions.

Invasive Alert: Tropical milkweed is invasive across many tropical and subtropical regions of the Americas, Australia and Asia, as well as in China, South East Asia and the Pacific.

Pronounciation: A-SCLE-pee-us cur-as-sa-VEE-ka

Hardiness zones
Sunset
12-24 (elsewhere as summer annual
USDA 9-11 (elsewhere as summer annual)

Landscape Use: Seasonal accent plant for mesic and tropical landscape themes, pollinator gardens.

Form & Character: Erect, stiff, open, airy, warm, cheerful, tropical, tender, informal.

Growth Habit: Evergreen, mostly herbaceous, perennial subshrub with a moderate, upright growth rate to 4-feet tall with less than equal spread. If it's irrigated regularly it will respond with increased vigor and size.

Foliage/Texture: Elongated, medium green, lanceolate leaves to 3-inches long with a prominent mid-vein, nearly sessile, opposite; medium texture.

Flowers & Fruits: Small, terminal yellow, orange to red flowers forming flat-topped umbels during spring through fall. Fruits are horn-shaped follicles to 3-inches long, seeds hairy.

Seasonal Color: Colorful flower accent during growing season, most intense in spring.

Temperature: Very heat tolerant, cold tolerant to 28oF.

Light: Full sun, but in Phoenix needs protection from summer western sun.

Soil: Tolerant.

Watering: Requires regular supplemental irrigation in lower desert gardens.

Pruning: Head back moderately to rejuvenate every 2 to 3 years.

Propagation: Seed, stem cuttings.

Disease and Pests: Aphids

Additional comments: Tropical Milkweed is great for Phoenix habitat and pollinator gardens. It attracts hummingbirds, butterflies and bees, and in particular is a forage source for the monarch and striated queen butterflies. Notable tropical milkweed cultivars include 'Red Butterfly' and 'Silky Gold'.

Poison alert: Tropical milkweed is poisonus to humans, dogs, cats, and livestock. So people, DO NOT ever use tropical milkweed as a salad garnish.

Minor taxonomic factoid: The genus Asclepias is named after the greek god Asklepios, the ancient god of medicine.