One of the most graceful plants that can enhance your outdoor garden is also one of the easiest houseplants to grow: the calla lily, which isn’t really a lily, nor is it a calla, although it is related to the latter genus. In reality, the calla lily is the common name for the zantedeschia genus; just as our family trees can be at times daunting in their complexities, so too with our favorite flowers. The genus calla was originally named by the famous Swedish botanist Carolus Linnaeus, but when the German botanist Karl Koch realized that it had become apparent that the genus needed to be split up, he honored his fellow Italian botanist Giovanni Zantedeschi by naming the new genus after him. The Europeans quickly recognized the value of this new flower, and it became a popular favorite for both weddings (as it signifies magnificence and beauty) and funerals.
What a unique and lovely houseplant the calla lily is! It loves 70 degrees Fahrenheit, which is the temperature at which most households are kept. Add a sunny location, evenly moist soil, and a water soluble fertilizer applied according to package directions during periods of new growth, and you’ll have a very happy member of your family! If you are starting from bulbs, plant them 2 to 3 inches deep, and space them 12 inches apart. You might want to employ several containers if you are enjoying them as houseplants.
As the blooms begin to wither, remove them, and gradually reduce watering until the foliage dies. Rest the tubers for 2 to 3 months without moisture, then repot and lightly water until the new plant is several inches above the soil line. If you prefer them indoors, no matter where you live, you will be able to enjoy near year-long blooms. Or, you can also enjoy them indoors, then move them outside during warm weather for garden enhancement.
We know that we can enjoy this fascinating flower indoors. Now we’re going to talk about how to enjoy the calla outdoors. Perennial bulbs, or rhizomes, calla lilies can grow to a height of from 1.5 to 4 feet with long, rich green leaves. While white is normally associated with this flower, they actually come in a wide variety of colors, from white to pink, purple, yellow, orange, and even black! They are tolerant of most pests and diseases, and are suitable for cut flower gardens, or planting en masse in beds, low borders, patio pots or planters. As with most plants, they will appreciate a cover of mulch, which holds in the moisture and keeps weeds at bay.
While their normal blooming time is listed as late spring, this northern gardener finds that they thrive throughout the summer outdoors, until close to the first deep frost. If you live in USDA zones 8 through 10, they are perennials outdoors and will not require indoor storage. In colder climes, after the foliage has withered away, dig up the long-fingered tubers, storing them in a breathable bag in perlite, peat moss, or vermiculite. When frost danger has passed, you may then transplant them outside, fertilizing with a 5-10-10 or 5-10-5 mixture.
One caveat: as calla lilies contain a poisonous ingredient called oxalic acid, keep children and pets away from your plants. With this simple precaution, you’ll have a perennial that you may enjoy indoors and then place outdoors after the ground has warmed.