Calla lily, also known as arum lily, is not a true lily. It belongs to the genus Zantedeschia which originates from South Africa. With huge, exotic looking flower-like spathes now available in a wide range of colours, calla lily is becoming increasingly popular as a house plant as well as a garden and patio plant.
Calla lillies flower from early to late summer on sturdy upright stems. Handsome foliage adds to their ornamental value – the lush leaves are wide and bright green, often speckled with white or silver. Most calla lilies are frost tender and the rhizomes or fleshy roots can be stored over winter and then replanted the following spring. The exception is white arum lily (Zantedeschia aethiopica) which is hardy outside in mild areas.
Watch out for confusion with the hardy pond plant bog arum (Calla palustris). Although the name and the white blooms may be similar, Calla palustris needs to be grown in shallow water at the edge of a pond.
How to grow calla lilies
Buy calla lilies as rhizomes or as pot-grown plants, to grow in pots of peat-free multi-purpose compost in a sunny frost-free spot indoors or outside. Keep watered and feed regularly, then bring indoors in autumn to overwinter before replanting the following year.
Growing calla lilies: jump links
- Planting calla lily
- Caring for calla lily
- Propagating calla lily
- Growing calla lily: problem-solving
- Where to buy calla lilies
- Calla lilies to grow
Where to grow calla lily
Frost-free conditions are essential as calla lily hybrids are tender. Grow on a well-lit windowsill, in a conservatory or a heated greenhouse. Once all risk of frost has past, calla lilies can be grown in the garden, in pots or in a border. A bright well-lit spot out of the strongest midday sun is ideal. Avoid full shade, but plants will tolerate partial shade. Calla lily must be sheltered from wind.
How to plant calla lily
Calla lily grows from thick rhizomes or fleshy roots that are sold when dormant in winter or spring. Ready-grown plants can be bought in spring and summer, often when in full flower.
To grow from dormant rhizomes, buy in winter or spring and plant 8-10 cm deep in a good, peat-free multi-purpose potting compost. Either pot up and start into growth indoors for earlier flowers, or plant outside after the frosts. Plants raised indoors need to be gradually hardened off or acclimatised to the outdoors by standing out for increasing periods of time.
If growing calla lillies in the ground, improve soil by adding plenty of well-rotted compost or a proprietary soil conditioner. Space plants 30-45 cm apart.
How to care for calla lily
Regular watering is important to maintain the handsome lush growth of calla lilies. Ideally, keep compost moist but take care not to over-water either. Once flowering shoots of calla lily appear, feed every three to four weeks with a liquid fertilizer high in potash, such as liquid tomato fertilizer. Regularly remove dead and faded flower stems and leaves.
Once flowering has finished, continue feeding and watering calla lily for several weeks, still taking care not to over-water, until the leaves start to die back. Bring potted plants indoors before the frosts and leave in the pot whilst dormant. Calla lilies growing in the ground should be dug up and the rhizomes stored in trays of just-moist compost for the winter, in a cool frost-free place. In late winter, repot the roots into moist compost and place in a warm spot to start into growth.
How to propagate calla lily
Divide calla lily rhizomes in late winter, before replanting.
Growing calla lily: problem solving
Calla lilies are easy to grow and mainly trouble-free.
Aphids may be a problem, particularly on plants growing indoors. Inspect leaf undersides regularly and also look out for a sticky substance on the surface beneath the plant: this is honeydew, which is produced by aphids and other pests. A variety of treatments can be used to combat aphids, though often hand-squashing is all that’s necessary if the pest is spotted early.
Advice on buying calla lilies
- Choose from a range of hybrid calla lilies with different coloured flowers, or white calla lily, which is hardier and can be grown outside in mild regions.
- Check plants over to make sure they look healthy and have no signs of damage or disease
Where to buy calla lilies online
Calla lily varieties to grow
- Zantedeschia ‘Captain Romance’ is a rich pink with large green leaves splashed with white.
- Zantedeschia ‘Garnet Glow’ has showy hot-pink flowers above bright green leaves.
- Zantedeschia ‘Ice Dancer’ bears pure white flowers above silver-splashed bright green leaves.
- Zantedeschia ‘Odessa’ has almost black flowers that make a striking contrast to the silver-flecked foliage.
- Zantedeschia ‘Picasso’ is unusually bicoloured, the spathes purple in the centre with cream edges, and white-spotted leaves.
- Zantedeschia aethiopica has white flowers and can be grown outside all year round in mild areas, in moist soil that doesn’t dry out. Grow in pots, in the ground or at the pond edge. Pure white flowers are borne from late spring into summer, above large, glossy, arrow-shaped leaves.