Calla lily bulbs are the usual way to propagate this plant. They are usually separated from a mother plant and planted in the spring when the threat of frost has passed and the soil has warmed sufficiently. Given reasonably good care, each bulb will produce up to six blossoms during its flowering season.
Although it is possible to start growing calla lilies from seeds, they take very long to germinate and have a very low success rate. It is best to begin growing calla lily using bulbs. If you are buying a calla lily bulb, there are usually two sides – a smooth and a bumpier side. The latter has little circular areas producing shoots or growing tips. Check for growing tips before buying a calla lily bulb. Calla lilies are tropical plants that crave heat. Air temperatures should be reliably above 55°F at planting time—and beyond.
Once you have your Calla lily bulb, here is how to plant it:
- Planting – choose a sunny spot in your garden since calla lilies grow well in warm areas. Plant bulbs so the side with the growing tips faces up. The ideal spacing for this plant should be at least 12 inches apart. For the best results, bury the tubers three to 4 inches below the surface of the soil that is rich in organic matter and drains well. Mulch soil once calla lilies are up and growing to keep roots on the cool side.
- Watering – Callas need plenty of water all during their growth cycle. Regular watering will ensure that the soil remains moist and the calla lilies hydrated all the time. However, do not overwater as the bulbs may rot. A presence of dark leaf tips indicates an overwatered calla lily.
- Fertilizer – You can use soluble all-purpose plant fertilizer as well as bulb fertilizer every month. You should apply the fertilizer more regularly when you start noticing development of flowers. However, you should stop fertilizing when the plant has already bloomed.
- Flowers appear in summer and linger about two weeks. You should stop feeding and watering the plant at the end of its growing season. This will allow the soil to dry and the lilies to die off. The calla lilies need to go into a period of winter dormancy for them to bloom again the following year.
How to store calla lily bulbs:
- Dig the calla lily out of the ground before the first frost by grabbing the plant close to the base. Rock it back and forth to loosen the soil at the base of the tuber. You may place it under cool-running water to rinse away the soil.
- Cut all the remaining plant material and inflorescences at about 2 to 3 inches. Then lay the tubers in the sun to dry for 3 days to a week.
- Store them about 1 inch apart in a dry peat moss inside a paper bag or cardboard box and place in a room kept at 50 to 55 degrees Fahrenheit until the danger of frost ends in spring.
- Check at the callas every week or two during winter and look for signs of drying, wrinkling and shrinking. Spray the peat moss a few times with water from a spray bottle if your rhizomes look a bit dry.