Calla Lily, Zantedeschia ssp., is a highly ornamental plant in the Arum family. They can be planted outdoors as part of naturalized woodland gardens or near ponds and streams where they thrive in the consistently moist soil. In areas with cold winters, Calla lilies can be grown in pots and treated as a houseplant. Bring the pot outdoors for the summer months to ensure abundant blooms.
White Calla Lilies, or Zantedeschia aethiopica, are the hardiest of the family and can tolerate hard freezes. The colored types are typically hardy in USDA growing zones 8-10 and may rot outdoors during cold, wet winters. Gardeners in other areas have the option of growing Calla Lilies as an annual or overwintering the plants indoors in a bright sunny window.
Calla Lilies are versatile and able to grow in both full sun or mostly shaded locations with well-drained but consistently moist soil. Deep, rich soil is ideal for good flowering and a heavy display of foliage. Plant Calla Lilies near water features like a stream or pond for an added vertical element amongst other marginal plants. Containers full of Callas in dramatic dark shades can be used to add a modern and elegant feel to an outdoor seating area. The plants will bloom for a long period between May and July.
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Shrubs To Plant With Calla Lily
Shrubs that like moist soil in full sun to partially shaded locations can provide a good backdrop for the dramatic spathe flowers of Calla Lilies. Early blooming deciduous shrubs like Deutzia, Forsythia, and Lilac add not only a solid green backdrop but subtle color to contrast or highlight the bold colors of Calla Lilies. Broadleaf evergreens such as Pieris, Camellia, and Leucothoe thrive in moist soil that drains well, which is ideal for growing Calla lilies.
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Perennials To Plant With Calla Lily
A wide variety of herbaceous perennials pair well with Calla lily. The trick to finding just the right companion is to seek plants that have the same growing preferences. Shade lovers that thrive in dampish soil include gunnera, elephant ear, ferns, hostas, astilbe, and bugleweed. The strong foliage shapes of all these plants make a lovely contrast with the long and upright shape of Calla Lily. Calla Lily also looks great planted amongst other sun-loving summer bulbs like gladiolus, dahlia, and alliums. Many of the newer colored Calla Lilies thrive in the drier, sandy soils that these plants prefer.
Ensure that the garden bed has excellent drainage, especially in the winter months, so that the rhizomes of these plants do not degrade or rot in cold wet soil and continue to thrive for many years.
Annuals To Plant with Calla Lily
Annual plants can be a bit tricky to plant in moist conditions with Calla Lilies. Most of the shallow-rooted annuals will be better suited to growing with Calla Lilies in containers. A few bedding annuals would make a good groundcover for Calla Lilies including New Guinea Impatiens, Heliotrope, Lobelia, and Dichondra. These plants have strong colors and shapes that make brilliant counterpoints to the elegance of Calla lilies.
Amend the planting area with a slow-release, granular fertilizer to make feeding the annuals easier and more consistent through the growing season. This also prevents overfertilization of the Calla Lilies, which often leads to a reduction in flowering and an increase in foliage.
Best Companion Plants For Calla Lily in Containers
Calla lily looks great growing in containers for decorating outdoor seating areas or adding a touch of class to your front entryway. The deep-growing roots of Calla Lilies will not compete with more shallow-rooted annuals and a few herbaceous perennials. Calla Lilies make natural thrillers so look for plants to fill the roles of spiller and filler. To complement the Calla Lily blooms, use asparagus fern, Dichondra, creeping Jenny, or ivy leaf geranium for texture and add Calibrachoa for color. All plants will grow well in sun to part shade.
Regular watering is very important for container-grown Calla Lily. The soil needs to remain moist while allowing excess water to drain. Use an all-purpose potting mix combined with organic compost at a ratio of 2:1. Adding a bulky organic material like finely shredded arborist chips will increase drainage without compromising moisture retention.
Plants Not To Grow With Calla Lily
Plants that thrive in the driest and hottest locations of your garden will not be compatible with Calla Lily. Xeric plants like prickly pear cactus, most ornamental grasses, sedum, yuccas, and aloes will not grow well with Calla Lily in consistently moist soil. Meadow plants that thrive in poor soils, such as coneflowers, yarrow, cosmos, and black-eyed Susan, are also unsuitable companions. Calla Lily tends to struggle in poor soil.
Best Plants To Grow With Calla Lily
Calla Lily is a great addition to any garden that has moist and well-draining soil. Pondside plantings with candelabra primrose, large-leaved Gunnera, butterbur, or marsh marigold will best meet the needs of Calla Lily and offer stunning foliage textures. For a bright tropical look, plant Calla Lily with crocosmia, Podocarpus, and bush lily in dampish soil and partial sun exposure.
Sources: “Zantedeschia aethiopica.” Missouri Botanical Garden. missouribotanicalgarden.org