Calla lilies are gracefully-shaped flowers that are sought after for both special occasion bouquets and beautiful home gardens. The blooms are truly timeless, and calla lilies have a storied history, including mentions in Greek and Roman mythology, where they were tied to both Hera, the goddess of marriage and birth, and Venus, the goddess of love and beauty.
Native to Africa, calla lilies also grow in other tropical climates, but can sometimes be considered invasive, specifically in Western Australia and some areas of the southern United States. The blooms come in a range of colors, from white and pale pink to deep burgundy, with some recent hybrids in dramatic colors like bright orange and black. They are a long-lasting cut flower and are popular in floral arrangements for this reason, especially when it comes to weddings.
When growing calla lilies for yourself, be sure to plant them in the springtime. They will grow moderately fast, often producing flowers by early-to-mid-summer and blooming throughout the season until early fall.
Calla lilies are easy to grow outside, as long as you live in USDA hardiness zones 8 – 10. They grow from a rhizome, not from a bulb, which is a key indicator that they’re not actually true lilies. Calla lilies will die back in summer and regrow each year, but in colder zones, you can plant calla lilies as an annual. By doing so, you’ll have to either dig up and overwinter the rhizomes or buy new rhizomes each growing season.
True to their tropical nature, calla lilies thrive in a warm environment, which includes plenty of light. If you live in an area that boasts hot and humid summer weather, your calla lilies will probably do better in a spot that experiences partial shade, while calla lilies grown in a slightly more temperate summer climate can handle full sunlight.
A rich, moist, well-drained soil is best to keep calla lilies blooming. Calla lilies often do well growing alongside ponds and can happily tolerate a moist soil location, though you should avoid allowing them to become waterlogged, which can lead to root rot. To increase the nutritional density of your soil, you can amend it with organic matter before planting your flowers.
Don’t water your calla lilies too heavily, especially after initially planting them. Once the rhizomes are established, you can water the plants once a week, or more frequently if experiencing especially hot or drought-like conditions. Calla lily plants potted indoors will need constant moisture, as pots will dry out sooner than ground plantings.
Temperature and Humidity
Calla lilies like a fairly warm environment and temperatures that range between 60 and 80 degrees Fahrenheit are ideal for them. They also enjoy a decent amount of humidity and moisture, so humid summers keep the flowers blooming just fine. If temperatures go much below 50 degrees Fahrenheit, the plants will tend to go dormant. If you want to dig up your rhizomes for overwintering, do so before temperatures go below freezing in your area in the fall.
Calla lilies need feeding upon planting, and again every spring at the beginning of their growing season, in order to promote bountiful flowering. Most well-balanced fertilizers will work just fine, but avoid choosing a blend with too much nitrogen, which can reduce the plant’s flowering.
Are Calla Lilies Toxic?
Unfortunately, calla lilies, as well as other flowers in the arum family (including philodendron and arisaema) are considered toxic to pets like cats and dogs. The blooms contain raphides, a form of calcium oxalate crystals, in all parts of the plant, which can cause issues ranging from mild discomfort to serious illness in pets.1 If you notice your pet exhibiting any of the below symptoms, contact a vet or emergency services immediately.
Symptoms of Poisoning
- Swelling of the mouth, including tongue, lips, and gums
- Trouble breathing
- Trouble swallowing
- Excessive drooling
- Pawing at the mouth or face
- Foaming at the mouth
Potting and Repotting
One indication that your calla lilies are ready for a bigger pot is if the roots look slightly crowded. Root-bound plants are not likely to thrive, so you should replant your blooms if you notice an issue with their roots.
Repotting calla lilies is actually pretty easy—to do so, carefully lift the flowers out of their smaller pot and gently place them into the larger one taking care not to damage the delicate roots. Fill the new pot with soil up to about an inch from the pot’s rim. Calla lilies need to be kept moist for a few days after repotting, so make sure to keep an eye on the soil’s moisture levels.
Common Pests & Diseases
There are several issues you may have to contend with when growing calla lilies, most notably bacterial soft rot, which affects the rhizomes, and botrytis, which is a fungal disease that causes a filmy grey mold to grow over the plant’s petals, stems, and leaves. To reduce the risk of fungal diseases, be mindful of watering frequency, and be sure to plant your calla lilies far enough apart so that they have ample air circulation.
Various pests can also be an issue for calla lilies, including insects like aphids, slugs, and spider mites. To combat these issues, treat the plants with a mild insecticidal soap or horticultural oil like neem oil.
Information courtesy of TheSpruce.com