How to Care for Calla Lilies

The Zantedeschia aethiopica is otherwise known as the Calla Lily or Arum Lily. Despite its name, it is not actually a lily, as it does not grow from a bulb but rather a rhizome.  

Growing in warm and moist conditions in Southern Africa, the Calla Lily has its roots in Greek mythology with “calla” meaning beautiful in Greek, and it is not difficult to see why! The Calla Lily forms elegant, glossy and arrow-like leaves that can either be plain or spotted in nature which unfurl around trumpet-shaped flowers otherwise known as spathes. These flowers range in colors of yellow, pink, purple, dark red, or black with tiny spike-like flowers otherwise known as spadix at the center. A symbol of love and femininity, the Calla Lily remains a popular cut flower for wedding bouquets and romantic occasions.

CALLA LILY LIGHT REQUIREMENTS:

The Calla Lily likes to be set in a position with filtered to indirect full sun - an east or west facing window sill would be perfect but it will not thrive in the shade. If the position has too much direct sun, the flowers and leaves will start to turn brown and brittle at the edges. In this case it should be moved to a more sheltered spot. In the winter, once the leaves start dying down, transfer the Calla Lily to a dark but well ventilated spot to give it the rest it deserves!

CALLA LILY WATER REQUIREMENTS:

As these are tropical plants, Calla Lilies do best in warm and moist soil. From late spring to late summer make sure to keep the soil moist by watering once a week; Do not let it become waterlogged as this can lead to the rhizome and roots rotting. During the winter months, the Calla Lily will not require as much watering and can be kept almost dry.

CALLA LILY TEMPERATURE REQUIREMENTS:

The ideal temperature range for the Calla Lily is 50-68℉. If the temperature becomes lower than this, it can force the plant into dormancy and can stop it from flowering.

During the winter the Calla Lily should be kept at a lower temperature (50℉), so that it can go into dormancy but protect from the frost at all costs! Over the winter, keep your Calla Lily in a dark and dry spot and allow the leaves to die down. It may look a little sad but do not worry, your Calla Lily will come back to life in the spring well rested and rejuvenated!

CALLA LILY  HUMIDITY REQUIREMENTS:

In their natural habitat Calla Lilies grow by water on the banks of rivers and streams or in marshlands which is why they grow best in higher humidity. They prefer humidity levels of 65-75%, anything less than this can cause the leaves to dry out and become brown and brittle.

In the winter, when the plant is in dormancy , humidity is not so important. Which means your Calla Lily can tolerate low humidity levels and lower temperature. But remember, you must protect your plant from frost!

CALLA LILY SOIL:

Calla Lilies love a dense, rich and moist compost similar to what is found in their native habitat. It is very important however, to make sure that there is sufficient drainage because if the soil becomes waterlogged, it can lead to rhizome and root rot.

CALLA LILY FERTILIZER:

Use a liquid fertilizer every two weeks from spring until the flowers start to fade. Once the Calla Lily stops flowering and goes into dormancy for its winter break, you can pause feeding until the spring.

CALLA LILY REPOTTING:

A good sign that your Calla Lily needs to be repotted is if you can see roots poking out of the bottom of the pot, or if the Calla Lily stops flowering. Don’t go too big too soon; repot the Calla Lily into a pot that is 3 or so inches larger than the previous pot. Take the plant with as much of the original soil as possible and backfill the rest of the pot with fresh, rich compost. Keep well watered for the first few days to give it a good start!

CALLA LILY PROPAGATION:

It is not recommended to propagate a Calla Lily too often, as this can lead to smaller and weaker plants with less flowering potential. However, if your plant is becoming pot bound or if a large mass of rhizomes have formed, nothing could be simpler than propagation!

Calla Lilies form a cluster of rhizomes that can be easily separated in late summer through early fall after it has flowered. Remove the mass of rhizomes from the pot and shake off any soil and take off the foliage. Divide the rhizomes, throwing away any that look weak and shriveled, only keeping ones that have an “eye”, as this is where the new plant will grow from. Keep the new rhizomes somewhere dark and dry until the division wound has healed over and then pot up and give a good water. You can then treat them as you would an established Calla Lily over winter. 

CALLA LILY COMMON PESTS/DISEASES:

Most diseases are linked to overwatering so make sure that the pot has good drainage to avoid root rot or botrytis. This very often shows itself as a fine mold covering the stems, leaves and flowers. Mold or fungus is also a sign of poor air circulation or the roots becoming pot bound and not being able to take up enough water so check the positioning of the plant and double check if any roots are poking out of the bottom of the pot. Calla Lilies are generally very resistant but this does not stop aphids, red spider mites or thrips (thunder bugs) attacking who can then also transfer viruses and diseases from plant to plant. Keep these pests away with neem oil or an insecticide making sure to follow the instructions on the packaging!