Roostertree (Calotropis procera)
The Roostertree (Calotropis procera) is a low-maintenance evergreen shrub/small tree thriving in hot, dry conditions.
Complete Plant Information
Overview
The Roostertree (Calotropis procera) is a distinctive, milky-sapped evergreen shrub or small tree best suited for warm, dry climates. Valued for its low maintenance requirements, this plant easily adapts to harsh conditions, making it highly practical for xeriscaping or utility planting where permanence is key. Its waxy, crown-like flowers provide year-round visual interest in regions where it is hardy.
This fast-growing species typically reaches 6 to 8 feet tall but can occasionally reach 15 feet. As a member of the milkweed family (Apocynaceae), Calotropis procera handles heat and drought exceptionally well once established. Gardeners appreciate its tolerance for poor, salty soils, although caution is advised due to its toxic latex sap.
Ultimately, Calotropis procera serves excellent functional roles, often utilized as a screening hedge or a unique specimen plant. Its unusual blooms and hardy nature ensure that the Roostertree remains a noteworthy addition to tropical and subtropical landscapes.
Fast Facts
- Plant Family: Apocynaceae
- Plant Type: Broadleaf evergreen
- Native Range: Africa, Asia
- Hardiness Zones: USDA Zones 10-11
- Size at Maturity:
- Height: 6-8 ft
- Spread: 6-8 ft
- Bloom Time: Seasonal bloomer
- Bloom Description: Pale purple to white
- Sun Exposure: Full sun to part shade
- Water Needs: Dry to medium
- Maintenance Level: Low
How to Grow
Planting the Roostertree is best done when temperatures are warm, allowing the stout taproot system time to establish before encountering cooler weather. It thrives in nearly any soil type, provided it is well-draining, though it exhibits excellent tolerance for dry, poor, or saline environments. Ensure it receives full sun exposure for the best flowering, though it can tolerate light afternoon shade during extreme summers.
Care for Calotropis procera once established is minimal. Water sparingly, only allowing the soil to become dry to medium between deep irrigation sessions. Fertilization is generally unnecessary due to its adaptation to low-fertility soils. Pruning is mainly required to maintain shape or for removing spent limbs.
A critical management note for sustained control involves the fruit. The large pods split open in the fall, dispersing numerous wind-blown seeds readily, which can contribute to invasive spread in pastures. To prevent this, remove developing seed pods before they fully mature and split. Remember that cutting stems releases a potent milky white sap (latex) that is toxic and irritating to skin, eyes, and sinuses; always wear protective gear when pruning this Roostertree.
Landscape Uses
The Roostertree is highly recommended where winter hardy, most commonly employed as a dense hedge due to its spreading, upright structure, often reaching 6 to 8 feet. It can also be trained into a charming small tree form, offering vertical structure in warm gardens. If you reside outside Zones 10-11, Calotropis procera can still be enjoyed by incorporating it into large containers, which must then be moved indoors to protect them from frost during winter dormancy.
Its tolerance for salt makes the Roostertree an excellent choice for coastal landscape screening or plantings near driveways where de-icing salts might be a concern. Though less common in formal borders, its large, waxy flowers and unusual foliage provide textural contrast against finer-leaved plants. Use it in mixed tropical borders or as a backdrop where a permanent, drought-tolerant screen is needed.
Standout Features
Flower Qualities
- Showy
Fruit Qualities
- Showy
Noteworthy Characteristics
Calotropis procera, commonly called small crownflower or giant milkweed, is an upright, spreading, milky-sapped, evergreen shrub or small tree of the milkweed family that typically grows to 6-8’ tall. Noteworthy features include oblong-obovate, light to dark green leaves and waxy, shallowly campanulate (crown-like) flowers that bloom throughout the year. A highly unique feature is the milky white sap (latex) released when stems are cut, which serves as a defense mechanism against pests.
Tolerances
- Drought
- Dry Soil
Potential Problems
The Calotropis procera generally suffers from few serious insect or disease issues, attesting to its robust nature. However, gardeners in certain areas may observe aphid infestations that can defoliate branches. The greatest threat to human and animal health comes from the plant’s sap; contact with eyes can cause painful, severe inflammations. Furthermore, be mindful of its tendency to escape cultivation; it can become invasive in pastures and rangelands if prolific seed production is not controlled by removing developing pods.
Frequently Asked Questions
What hardiness zones is Roostertree suitable for?
The Roostertree, Calotropis procera, is winter hardy only in USDA Zones 10 and 11.
How large does Roostertree grow?
This shrub/small tree typically matures to a height and spread between 6 and 8 feet, although it can occasionally reach 15 feet under optimal conditions.
What sun exposure does Calotropis procera need?
Calotropis procera thrives best when situated in full sun, though it adapts well to partial shade environments.
When does Calotropis procera bloom?
This plant is a seasonal bloomer, offering flowers described as pale purple to white throughout the year in suitable climates.
Conclusion
The Roostertree (Calotropis procera) offers significant value to gardeners in warm climates seeking a tough, low-maintenance evergreen screen. Its adaptability to drought and poor soil, combined with its unique blooms, establishes it as a distinctive landscape element, provided its sap toxicity and invasive seed potential are managed responsibly. Before planting, confirm your site falls within USDA Zones 10–11 to ensure this hardy plant thrives long-term.
Wildlife Benefits
As a member of the milkweed family, Calotropis procera holds significant ecological value, specifically noted as a larval host plant for monarch butterflies. While it is not the primary milkweed species for many areas, providing native host resources is vital for supporting the monarch life cycle. Utilizing this plant responsibly, while being mindful of controlling seed dispersal, allows gardeners to benefit from its aesthetic appeal while supporting local pollinator populations.
Propagation Tips
The primary methods for propagating the Roostertree in cultivation are by seed or cuttings. Cuttings taken from semi-ripe wood can be rooted, though results can vary depending on species and environmental conditions. Seeds, found within the inflated pods, are numerous and utilize a silky white pappus for wind dispersal upon ripening. If propagation is not desired, prompt removal of developing fruit is the best way to prevent accidental spreading of Calotropis procera.
