The Arum family (Araceae) is a vast group of flowering plants, with approximately 110 genera and 1,800 species. Many are popular indoor plants due to their striking foliage and adaptability. They are known for their distinctive inflorescence, featuring a fleshy central column (spadix) often surrounded by a modified, brightly colored leaf (spathe).
Identifying Common Arum Family Houseplants
The Arum family is home to many beloved houseplants, each with unique visual characteristics. Monstera deliciosa, the Swiss Cheese Plant, is recognized by its large, glossy, deep green leaves that develop distinctive natural splits and holes as they mature. These fenestrations are a key identifying feature. Philodendron hederaceum, or Heartleaf Philodendron, displays bright, glossy, heart-shaped, dark green leaves that may have a bronze tint when emerging. This climbing vine often trails from pots or can be trained to climb supports.
Epipremnum aureum, known as Pothos or Devil’s Ivy, features heart-shaped leaves, often variegated with yellow or white patterns. This plant is a versatile climber or trailing vine. The Peace Lily (Spathiphyllum) is recognized by its dark green leaves and distinctive white, hood-like spathes that enclose a creamy white spadix. These plants produce their blooms throughout the year.
The ZZ Plant (Zamioculcas zamiifolia) is easily identified by its thick, upright, fleshy stalks adorned with glossy, dark green, pinnately compound leaves. Alocasia species, often called Elephant Ear plants, are characterized by their large, often arrow-shaped or heart-shaped leaves that can be green, purple, or silver, frequently displaying prominent, contrasting veins.
Anthurium, sometimes called the Flamingo Flower, features large, heart-shaped leaves and distinctive inflorescences with a colorful, waxy spathe surrounding a central spadix. The spathes come in shades of red, pink, white, yellow, green, or orange, providing a vibrant display. Finally, Dieffenbachia, or Dumb Cane, has large, thick leaves that are a mixture of green, white, and yellow, with various variegation patterns. Its leaves are oval or lance-shaped.
General Care for Arum Family Houseplants
Arum family houseplants thrive with proper care. Understanding their preferences for light, water, soil, temperature, humidity, and fertilization is important for their health.
Light
Most Arum family plants prefer bright, indirect light indoors. Direct sunlight can scorch leaves, causing discoloration or damage. Insufficient light leads to leggy growth, smaller leaves, or reduced variegation. An east-facing window is often ideal, or a few feet from a south or west-facing window, provides ample brightness without harsh direct exposure.
Watering
Proper watering prevents issues like root rot. Allow the top 1 to 2 inches of soil to dry completely between waterings. Thoroughly drench the soil until water drains from the bottom, then discard excess. Overwatering causes yellowing leaves and mushy stems; underwatering leads to drooping, wilting, or crispy leaves. Use dechlorinated water by letting tap water sit for at least 24 hours before use.
Soil
An ideal soil mix for Arum family houseplants is well-draining, airy, and rich in organic matter. A quality potting mix with perlite or orchid bark enhances drainage and aeration, preventing compaction and waterlogging. Good drainage is essential, as these plants are susceptible to root problems in overly wet conditions.
Temperature and Humidity
Arum plants thrive in warm indoor temperatures, 65 to 85°F (18 to 29°C). They are sensitive to cold temperatures and drafts, which can cause leaf drop or browning. As tropical plants, they appreciate higher humidity. To increase humidity, use a pebble tray, group plants, or employ a room humidifier. Misting foliage provides a temporary boost.
Fertilization
During the active growing season (spring and summer), Arum family houseplants benefit from regular fertilization. Apply a balanced liquid fertilizer, diluted to half strength, monthly. Avoid over-fertilizing, as this can lead to nutrient burn. Reduce or cease fertilization during the cooler, dormant months of fall and winter when growth slows.
Understanding Arum Plant Toxicity
Many Arum family plants contain calcium oxalate crystals, which cause their toxic properties. These needle-shaped crystals in the plant’s sap can cause irritation upon contact or ingestion. Ingested symptoms include immediate burning, irritation, and swelling of the mouth, tongue, and throat; difficulty swallowing or speaking may occur.
For pets, symptoms include oral irritation, excessive drooling, vomiting, and difficulty breathing. Exercise caution when handling these plants. Wear gloves, and wash hands thoroughly after touching them. Keep Arum family houseplants out of reach of children and pets.
Propagating Arum Houseplants
Propagating Arum family houseplants is a straightforward process, often achieved through stem cuttings. This method allows gardeners to easily multiply their favorite plants.
To propagate using stem cuttings, select a healthy stem with at least one or two nodes. Cut the stem just below a node using clean, sharp pruning shears. Place the cutting in water, ensuring nodes are submerged, or directly into a well-draining potting mix.
In water, roots form within a few weeks; once several inches long, transfer to soil. When planting directly in soil, maintain consistent moisture for new growth. For clump-forming varieties, propagation by division is an option, separating the plant into smaller sections, each with its own root system, for repotting.
Common Issues and Troubleshooting
Even with diligent care, Arum family houseplants can occasionally encounter problems. Recognizing the signs of distress and understanding how to address them can help maintain plant health.
Pests like spider mites, mealybugs, aphids, and scale insects can infest these plants. Regular inspection of leaves, especially the undersides, helps detect infestations early. Organic treatments such as insecticidal soap or neem oil control these pests.
Environmental stressors often manifest as visible changes in foliage. Yellowing leaves indicate overwatering or underwatering, while browning leaf tips point to low humidity or inconsistent watering. Stunted growth may suggest insufficient light or a nutrient deficiency, requiring adjustment in placement or fertilizer.
Fungal issues, such as root rot, are caused by overwatering and poor drainage. Ensuring well-draining potting mix and allowing soil to dry between waterings are the best preventive measures.