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.
Arum Lily vs Calla Lily Uncovering the Key Differences Between These Stunning Flowers
Gardeners are often confused about the differences between arum lily and calla lily, two plants that look quite similar at first glance Though related, these flowers have distinct origins, growth habits, ideal conditions and uses that set them apart.
By understanding the unique traits of each type of lily, you can make informed choices to enhance your landscape. This guide will explore all the key differences to know.
Origins and Family
Arum lily and calla lily both belong to the Araceae family of flowering plants. However, they are separate genera:
-
Arum lily: Zantedeschia aethiopica is native to southern Africa.
-
Calla lily: Zantedeschia elliottiana and Zantedeschia rehmannii hail from southern Africa as well. There are also hybrid calla lily cultivars.
Though they share a homeland, these plants evolved to thrive in diverse habitats and settings within the region.
Growth Pattern and Size
Arum lilies are clump-forming perennials with large, thick rhizomes. Arrowhead-shaped leaves emerge, followed by tall flower stalks up to 4 feet high. The large lily pads and sturdy stalks make arum lilies bold accent plants.
Calla lilies have more delicate, heart-shaped leaves and dainty blooms on shorter stems, growing just 1-3 feet tall. Their fine texture makes them ideal for borders, container gardens and cut flower arrangements.
Climate and Growing Conditions
Arum lilies relish shady, humid environments. They flourish in zones 7-10. Dappled sunlight and consistently moist soil are ideal. These tough plants even tolerate soggy soil or wet feet.
Calla lilies thrive in zones 8-11 and need full sun to part shade. Well-draining soil is essential to prevent rot in their tuberous roots. Callas suffer in heavy clay or perpetually soggy earth.
Watering needs also differ. Arum lilies enjoy constant moisture while callas require soil to dry out between waterings.
Flowers: Shape and Color
The unique blooms of both plants feature:
-
Spathe – A colored bract surrounding the flower spike.
-
Spadix – The spike of tiny real flowers.
For arum lilies, the yellow spadix protrudes prominently above the white spathe. With calla lilies, the spadix rests entirely within the spathe, which comes in diverse hues like pink, purple, orange, yellow and more.
Spread Rate and Invasiveness
Under optimum conditions, arum lilies spread rampantly by offsets and seed dispersal, colonizing large areas. Their aggressive growth enables them to disrupt native habitats, so they are banned in parts of Australia and New Zealand.
Calla lilies multiply slowly as their tubers produce small cormels. They lack invasive tendencies, making callas a prudent choice around natural areas.
Uses in the Landscape
Thanks to their bold structure, arum lilies make excellent backdrop plantings and privacy screens. They also thrive along ponds and streams.
Calla lilies are darlings of cottage gardens and mixed borders. Their colorful blooms shine in patios containers too. Callas work beautifully as cut flowers.
Ongoing Care Tips
Arum lilies need ample water and division every few years to curb overcrowding. Deadhead spent blooms and cut back plants through winter.
For callas, apply balanced fertilizer monthly during growth and water when the top inch of soil dries. After frost, dig up tubers to store indoors in cool, dry conditions.
Gardening with Lilies
Now that you understand the origins, growing needs, flowers, invasiveness potential and landscape uses of arum lily vs calla lily, you can make informed selections for your beds and borders.
Plant arum lilies in shaded, moist areas where their large leaves and flowers can take center stage without concerns over spread. Use clumping calla lilies to inject color in beds, along walks and in planters. They make lovely cut flowers too.
With their stunning blooms and lush foliage, both types of lilies can bring captivating beauty to your outdoor spaces. Choose the species best suited to your climate, landscape design and maintenance regimen. Then enjoy their bountiful floral displays.
Growing calla lily (Zantedeschia): 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.
How to grow calla lilies (Zantedeschia)
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.
Calla Lily Care Guide – Picking, Placing, and Parenting Your Plant
FAQ
What’s the difference between a lily and a calla lily?
As mentioned, although calla lilies are similar to regular lilies, they belong to a different plant family. Calla lilies are cultivars of an Araceae (arum) plant, while true lilies are polyploid members of the Liliaceae (lily) family, and they share only some visible characteristics.
What is another name for the arum lily?
Zantedeschia aethiopica, commonly known as calla lily and arum lily, is a species of flowering plant in the family Araceae, native to southern Africa in …
Are arum lilies poisonous to touch?
Human poisoning
Arum lily contains a mineral called calcium oxalate. All parts of the plant, especially the flower, are poisonous and can cause: eczema and dermatitis. irritation, burning and swelling of the mouth and throat.
Is Arum Lily the same as Peace Lily?
The peace lily isn’t actually a lily but an arum, and belongs to the same family as Zantedeschia and lords-and-ladies (Arum maculatum), as well as less obvious plants such as the Swiss cheese plant (Monstera deliciosa) and dumb cane (Dieffenbachia).
Are calla lilies the same as arum lily?
Calla lilies and arum lilies are both beautiful and elegant plants with similar structures. Both belong to the Araceae family. They are popular ornamental plants. Although they share many similarities, calla lily and arum lily are not the same. What is the difference between calla lily and and arum lily?
What is another name for a calla lily?
Another name for a calla lily is Zantedeschia, which refers to its scientific genus. These plants are also sometimes called “arum lilies” because they belong to the same family as the arum plant. 4. How do you identify a calla lily?
Are arum lilies Hardy?
Arum Lilies are hardy types and are larger and multiply faster. Calla Lilies are tender types. Arum Lilies are more tolerant of wet, shady environments than their sun-loving Calla Lily cousins. In this article, we’ll do a deep dive into the differences between Calla Lilies and Arum Lilies and discuss how Canna Lilies fit into the mix.
What are arum lilies called?
‘Arum Lily’ is used loosely as the common name for both the true arum lilies (Arum species) and the calla lilies, Zantedeschia species (Parsons & Cuthbertson 2001). Are arum lilies poisonous to touch?
What color are arum lilies?
The spathe of an Arum lily is usually pure white and can grow up to 25 cm long. It stands out against the yellow spadix in a striking way. Depending on the species and cultivar, calla lilies have a wider range of spathe colors, such as yellow, pink, purple, and even dark maroon. Arum Lilies:
Are arum lilies related?
Although the two are related and bear a strong resemblance, they differ in some important ways. In determining which is best for your garden, it’s worth knowing what these differences are. Arum lilies (Zantedeschia aethiopica in the family Araceae) are handsome and unusual plants.