Calla lilies (Zantedeschia spp.) are perennial plants that enter a dormant phase after their growing season. During dormancy, the plant's energy retreats into the bulb (technically a rhizome), preparing for the next growth cycle. Proper storage ensures the bulb remains healthy and viable for replanting.
Wait until the foliage turns yellow and dies back naturally, typically after the first frost in colder climates. This signals the plant has completed photosynthesis and stored sufficient energy in the bulb. Premature digging may weaken the bulb, reducing its chances of thriving next season.
Gently dig up the bulbs, taking care not to damage them. Shake off excess soil and rinse them with water to remove debris. Inspect for rot or pests, discarding any unhealthy bulbs. Allow the bulbs to air-dry in a shaded, well-ventilated area for 1–2 days to prevent mold during storage.
Trim away dead foliage and roots, leaving about 1–2 inches of stem to avoid injuring the bulb. Cure the bulbs by placing them in a warm (70–75°F or 21–24°C), dry location for 7–10 days. This step helps the outer layer toughen, reducing moisture loss and disease risk.
Store bulbs in a breathable medium such as peat moss, vermiculite, or dry sand. Avoid plastic bags, which trap moisture and promote rot. Place the bulbs in a single layer, ensuring they do not touch each other to prevent mold spread.
Calla lily bulbs require cool (50–60°F or 10–15°C), dark, and dry conditions. A basement, garage, or root cellar works well. Avoid freezing temperatures, as this can damage the bulb's cellular structure. Monitor humidity levels—excessive moisture may cause rot.
Check bulbs monthly for signs of shriveling, mold, or pests. If bulbs appear dry, lightly mist the storage medium. Discard any bulbs showing rot to prevent contamination. Healthy bulbs should remain firm and plump.
About 4–6 weeks before the last frost, reintroduce bulbs to warmth (65–70°F or 18–21°C) to break dormancy. Inspect again and soak healthy bulbs in water for 1–2 hours before planting to rehydrate them. Plant in well-draining soil once the danger of frost has passed.
In frost-free regions, calla lilies may remain in the ground year-round. Mulch lightly to protect bulbs from occasional cold snaps. If lifting bulbs is preferred, follow the same storage steps but reduce curing time due to higher ambient humidity.
