Bright green, oval leaves do not completely hide the sharp horns that make this succulent a focus of religious legend. Well suited to USDA hardiness zones 10a and 10b, this sun-lover flourishes outdoors if sheltered from unanticipated frost. Given proper care, Crown of Thorns blooms most of the year.
1. Choose a sunny location for your Crown of Thorns. Whether of the original Madagascar varieties, the larger California Giant hybrid or the new bushy, less gangly Thai hybrids, Crown of Thorns do best in the full-day sun of a southern exposure. Sun is essential to abundant and sustained blooming.
2. Plant the indoor Crown of Thorns in a good potting soil and provide thorough drainage for excessive water.
3. Water Crown of Thorns regularly. A weekly schedule is not excessive if soil is permitted to dry to the depth of an inch (2.5 cm) between waterings. Overwatering can result in spongy stems, leaf loss and failure to bloom.
In addition to testing soil for moisture, watch for leaf-droop as a signal that more water may be needed. Maintain this schedule throughout spring, summer and fall to maximize the chances of steady and prolonged blooming.
4. Fertilize the Crown of Thorns with full-strength, liquid fertilizer when you plant. After that, dilute fertilizer to half-strength and apply once a month during the spring, summer and fall.
5. Restrict water during winter months to rest the plant. Soil can dry completely and some leaves may shed between small waterings. Do not fertilize during this period. Do not mist. A three-month artificial winter provides adequate time for your plant to prepare for another extended blooming season.
Tip
Crown of Thorns are temperature-sensitive as well as highly reactive to moisture. A sudden chill or damp spell is first reflected in the absence of bloom. Experienced growers counsel consistent care and patience.
Source: sfgate.com
