There are over 32 varieties of arum in the family Araceae. What are arum plants? These unique plants are known for their arrow-shaped leaves and flower-like spathe and spadix. Most arums are not frost tolerant, as many are from the Mediterranean region; however, a few European varieties have some cold hardiness. Learn which common members of the arum plant family might thrive in your region and hardiness zone.
What are Arum Plants?
While calla lilies, also known as arum lilies, have the same showy spathe as plants in the arum family, they are not true members of the Araceae group. However, since they are very recognizable plants, their appearance helps explain what arum members look like with exception to height, spathe colors and leaf sizes. All types of arum plants are poisonous and may not be suitable in gardens with pets and children.
Arums are rhizome producing, perennial plants. Most hail from the Mediterranean but some species are also found in Europe, western to central Asia, and in northern Africa. Plants in this family range from nearly 8 inches up to nearly 2 feet in height (20-60 cm). Plants produce a modified leaf called a spathe that curves around the spadix, which is the source of the true flowers. Spathes may be violet, white, yellow or brown and may even be sweetly or sharply scented. Flowers develop into red or orange berries.
Arum Plant Information
Most arums prefer moist, well-draining soil, warm temperatures of 60 degrees F. or higher (nearly 16 C.), and rich soil with frequent fertilizing. It is fairly easy to propagate most varieties of arum by leaf cuttings, stem cuttings, layers or division. Planting by seed can be capricious at best.
Outside of temperate to tropical ranges, the cooler region gardener may not have much access to arum plant family members. Of the different types of arum plants seen commonly in the landscape, Jack-in the-pulpit has to be one of the hardiest and most widespread. This small plant eventually produces colonies and attractive white spathes.
Anthurium plants are arum plant members, often grown as a houseplant in cooler areas or landscaping plants in USDA zones 10 or higher. Plants in the arum family may also include arrowhead members, also commonly grown as houseplants in many places.
Another of the most common arums are the Lords and Ladies, or cuckoopint. Many of the available varieties of arum plants are not common, however, but you can try online nurseries for a broader selection. A European native, Italian arum is a medium sized plant with deeply veined leaves and a creamy white spathe.
There are many varieties of arum that are not directly in the Araceae family but simply grouped in for appearance and convenience. These include:
- Zantedeschia (calla lily)
- Spathiphyllum (peace lily)
- Colocasia (elephant ear)
Keep in mind that while they share characteristics with Araceae members, they are not true arums.