Calla lilies are unique and elegant flowering plants that make a spectacular addition to the home or garden. They're also popular choices for bridal bouquets and flower arrangements. White calla lilies are quite common, but green, pink, purple, yellow, and orange are also available. The colored flower types (Zantedeschia hybrida) are complex hybrids of different South African species and grow from deciduous tubers. These plants come from mountainous regions where temperatures are cool, but the ground never freezes. Native light levels are high and soil drains quickly.
- Determining the Top or Bottom of Bulb: The rounded side of the bulb is the bottom. The top side is the concave side where roots and leaves sprout.
- Sprouting Time: Expect sprouts within 4 – 6 weeks. If planted in the ground, it may take a little longer if the temperatures are still cold.
- Bulb Preparation: Plant immediately in pots. If planting in the garden, wait until ground is permanently thawed.
- Shelf Life: To ensure adequate blooming time, planting should occur by late June.
- Location in Garden & Spacing: Calla lilies prefer partial sun. Cover with only a couple inches of soil and space about 4" apart.
- Height & Width: Calla lilies are usually 15" – 24" tall and wide.
- Potted Plants: Plant one or two per 6" pot, or combine more in a larger pot.
- Soil: Use regular potting or garden soil.
- Watering: Upon planting, water immediately and then a couple times a week all summer.
- Fertilizer: This helps maintain flower size and count from year to year. For best results, use Roberta's Flower Magic Plant Food twice a month all summer.
- Lighting: Partial sun is preferable. Full sun stunts flower height, burning flowers and foliage.
- Temperature Zones 8 – 12: If planted in the ground, they'll come up at the right time without worry of frost damage. If planted in pots, place them outside and leave them there all summer as long as nights stay above 50°F.
- Winter Dormancy: In late autumn, cut plants back to the ground. No matter if they're in pots or in the garden, calla lilies can handle temperatures down to 35°F. If you live where it gets colder, place them in the garage or elsewhere to minimum temperature. Water lightly once a month in the winter.
- Propagating: Calla lily bulbs re-bloom every year from June to July. After 3 – 4 years (in spring or fall), divide bulbs into small divisions and replant.
Q: Help! My bulbs are slow to come up.
A: Make sure you planted them with shallow covering — only 1" – 2" of soil. Also, make sure that they were planted top-side up.
Q: Why are some of the flowers different sizes?
A: Each variety has a different size and height.
Q: Why are they blooming less than they used to?
A: Fertilize every year to help maintain flower size and count. For best results, use Roberta's Flower Magic Plant Food twice a month all summer. Otherwise, a standard well-balanced fertilizer normally used for houseplants will suffice.