GIANT MILKWEED CROWN FLOWER Calotropis

Milkweed is an essential perennial plant for the butterfly garden, and it is the ONLY plant that the monarch caterpillar can eat. The flowers also attracts many other butterflies!

Calotropis gigantea (crown flower) is a large shrub growing to 4 m (13 ft) tall. It has clusters of waxy flowers that are lavender in color. Each flower consists of five pointed petals and a small "crown" rising from the center which holds the stamens. The plant has oval, light green leaves and milky stem.

This plant plays host to a variety of insects and butterflies. It is the host plant for Hawaii's non-migratory monarch butterflies.

The flowers are long lasting, and in Thailand they are used in floral arrangements.

Calotropis is a poisonous plant. The leaves and stem when incised yield thick milky juice. During the process of making a Hawaiian lei flower necklace, touching the sap and then touching the ocular surface may result in crownflower keratitis. There is generally a complete resolution and a return to normal visual acuity. Applied to the skin, it causes redness and vesication. When taken orally, the juice produces an acrid, bitter taste and burning pain in throat and stomach, salivation, stomatitis, vomiting, diarrhea, dilated pupils, tetanic convulsions, collapse and death.

C. gigantea is reported to exhibit mosquito controlling properties. The aqueous extract of the leaves demonstrated significant larvicidal, repellent and ovicidal activity.

Type: Quick growing shrub

Location: Sun

Hardiness zones: 9-11, or in cooler regions can be brought indoors for winter, or grown as annual as they are fairly quick growing.

Height: 4m, 13' in warm climates, and up to 5' if grown as an annual. Plants can be overwintered indoors in pots.

Bloom time: Summer to fall

Note: This plant species is known to have toxicity. Ingestion of these seeds or this plant can cause illness such as vomiting or diarrhea.

Seeds per pack: 5

Germination: As with many perennial seeds, these seeds require a period of moist cold to help them break dormancy. This is done by giving them a cold 'winter' period (artificial or natural), and then a warming to simulate 'spring', and time to grow! Here's how this can be done:

Obtain a planting container that has holes in the bottom for excess water to drain. Place the seeds just under the surface of your growing medium, and water. Place your container in a cold area (but not freezing, perhaps a refrigerator) for 4-6 weeks. Once the cold period is completed, place the container at room temperature for them to germinate. Be sure to keep the soil moist during this entire germination period. Seedlings will sprout a few weeks, or occasionally several months, after the warming period.