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Giant Milk Weed

Giant Milk Weed

Calotropis gigantea

  • ​Common Name: Giant Milk Weed (other common names: Crown flower, giant calotrope, swallow-wort)
  • Scientific Name: Calotropis gigantea
  • Family Name: Apocynaceae
  • Origin: Native to Asia and Tropical Africa including Cambodia,Indonesia,Malaysia, the Philippines, Thailand, Sri Lanka, India, China, Pakistan, Nepal, and tropical Africa).
  • Height: 6’ – 16’
  • Width: 6’ - 8’
  • Growth: fast growing    
  • Zone: 10B - 11
  • Light Needs: Full sun.
  • Salt Tolerance: Moderate
  • Soil/PH/Texture: Prefers sandy, loamy and clay soils, well-drained soil but can grow in nutritionally poor soil as well. Suitable pH of soil: acidic - alkaline and can also grow in saline soils.
  • Soil Moisture: Average water needs, medium moisture, but do not overwater. For best growth and flower production soils should be consistent and with even moisture.
  • Drought Tolerance: Moderate
  • Pests/Diseases: No serious insect or disease problems.
  • Growing Conditions: Low maintenance has been known to thrive in soils where nothing else will grow.
  • Characteristics: This broadleaf evergreen shrub, is a succulent, with medium green leaves. It has showy flowers crown-like in shape, medium purple and white/near white, that appear in clusters and flowers nearly year-round.
  • Propagation: Stem cuttings and layering.
  • Wildlife: Attracts butterflies, bees and birds.
  • Facts: In Hawaii their flowers are commonly used for making Lei’s and in India the crown flower produces a durable fiber known as 'Bowstring of India' which is commonly used to make carpets and ropes. The toxic sap has been known to also make poisonous arrows. This plant is very important for Monarch butterflies for their larvae to eat from in order to finish their lifecycle. Although perfect for the butterfly the milky sap is toxic and can cause severe inflammation if it gets in your eyes, irritant to mucus membranes, and parts of plants are poisonous if they are ingested by humans. The crown flower though has antifungal and insecticidal properties and in traditional medicine used to treat many common treatments and diseases.
  • Designer Considerations: Great for xeriscaping and seaside gardens. Is suitable for 3 galllon pots or larger with excellent drainage for your patio or along your driveway. It can also be trained as a small tree, used as a specimen, screening, hedge or border.​

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