Caring for Potted Calla Lilies in California: Repotting, Blooming, and Spider Mite Control

Understanding Your Calla Lilies

Calla lilies (Zantedeschia) are perennial plants that thrive in mild climates like Santa Clara’s USDA Zone 9. The two main types are the large, evergreen white florist calla (Zantedeschia aethiopica) and the smaller, colorful deciduous hybrids that go dormant after blooming. Your plants — with pink and near-white flowers on 4- and 8-inch stems — are likely the colorful deciduous variety.

Repotting and Container Size

Your current 3-inch base pot is too small for two plants. Repot each rhizome into a 6- to 8-inch diameter container with well-draining, rich potting mix. Plant rhizomes horizontally, with the growing points (bulls-eyes) facing up, covered by 2 inches of soil. Water thoroughly after repotting.

Bloom Duration and Dormancy

Colored callas typically bloom for 4–8 weeks, depending on variety. After flowering, leaves will yellow and wither — this signals the start of dormancy. Reduce watering but keep the soil slightly moist. Store the pot in a cool (40–50°F), dark place for 2–3 months. Do not discard the plant; it will resprout when conditions improve.

Spider Mite Management

Spider mites dislike cool, humid conditions. Move the plant outdoors for a day — the mites will die off. When bringing it back inside, mist daily and increase humidity (e.g., place in the bathroom during showers). Repeat if needed.

Long-Term Care Tips

• Provide bright, indirect light and consistent moisture during active growth.
• Fertilize monthly with a balanced 12-12-12 fertilizer.
• In Zone 9, you can plant callas in the ground after the last frost; they will naturalize beautifully.
• Remember: all callas need a rest period. Patience during dormancy is key to success.