Botanical Classification
Calathea medallion, typically referring to Calathea roseopicta ‘Medallion’, is a member of the Marantaceae family, a group of tropical plants known as prayer plants due to their leaves’ nocturnal movement, folding up at night. It belongs to the genus Calathea, which includes numerous species and cultivars prized for their ornamental foliage. This herbaceous perennial is a hybrid cultivar, distinguished by its vibrant, medallion-like leaf patterns, making it a popular houseplant within the diverse Calathea genus.
History
Calathea medallion emerged as a cultivated variety of Calathea roseopicta in the late 20th or early 21st century, developed through selective breeding to enhance its striking foliage patterns. While Calathea roseopicta was introduced to European horticulture in the 19th century from South America, the ‘Medallion’ cultivar gained prominence with the modern houseplant boom, fueled by social media and interior design trends. Its bold, colorful leaves have made it a favorite among plant enthusiasts seeking a tropical aesthetic for indoor spaces.
Native Area
As a hybrid, Calathea medallion has no true native area, but its parent species, Calathea roseopicta, is native to the rainforests of South America, particularly Brazil and Colombia. It grows as an understory plant in humid, shaded environments with rich, well-draining soil under the forest canopy. These conditions shape the cultivar’s cultivation needs, making it ideal for indoor settings or shaded outdoor areas in frost-free climates where high humidity and filtered light can be provided.
Identifying Characteristics
Calathea medallion is renowned for its broad, oval leaves with a dark green perimeter and a vibrant, medallion-like center featuring shades of green, silver, and pinkish-purple, creating a bold, patterned effect. The undersides of the leaves are a rich burgundy, adding dramatic contrast. The leaves exhibit the characteristic prayer plant movement, folding slightly at night. Its clumping growth habit typically reaches 1–2 feet (30–60 cm) in height and spread, with insignificant flowers, as the foliage is the primary attraction.
Growth Rate and Lifespan
Calathea medallion has a moderate growth rate, forming a lush, bushy plant within a growing season under optimal conditions—high humidity, indirect light, and consistent moisture. With proper care, including protection from environmental stress and regular maintenance, it can live for 3–5 years or more as a houseplant. Its lifespan can be extended through propagation via rhizome division, allowing growers to rejuvenate or expand their collection.
USDA Zones
Calathea medallion thrives as a perennial in USDA Hardiness Zones 10–11, where it can be grown outdoors in frost-free, tropical or subtropical climates with temperatures between 65–80°F (18–27°C). It is highly sensitive to cold and cannot tolerate temperatures below 55°F (13°C). In zones 9 and below, it is typically grown as a houseplant or in greenhouses, where humidity and temperature can be controlled to replicate its native rainforest environment.
Common Uses
- Ornamental Houseplant: Prized for its vibrant, medallion-like foliage, it’s a popular choice for indoor plant collections, adding a tropical, colorful touch to homes or offices.
- Interior Decor: The bold leaf patterns and burgundy undersides complement modern or bohemian interior designs, often used as a focal point in decorative pots.
- Terrarium Plant: Suitable for large terrariums or enclosed glass containers due to its humidity-loving nature, showcasing its striking foliage.
- Collector’s Plant: Sought after by plant enthusiasts for its vivid patterns and prayer plant characteristics, appealing to specialized tropical collections.
- Propagation Projects: Frequently propagated via rhizome division, popular among hobbyists for expanding collections or sharing with others.
- Educational Use: Utilized in horticultural studies to teach about prayer plants, tropical plant care, and the development of hybrid cultivars.
Cultivation of Calathea medallion
- Light: Provide bright, indirect light to enhance the medallion-like leaf patterns. Place near a north- or east-facing window indoors or in a shaded outdoor area in suitable climates. Avoid direct sunlight, which can scorch the broad leaves, causing fading or burns.
- Temperature: Maintain temperatures between 65–80°F (18–27°C), ideal for its South American rainforest origins. Calathea Medallion is sensitive to cold and should be kept above 55°F (13°C) to prevent leaf curling or drop. Protect from drafts, heaters, or air conditioning vents.
- Humidity: Aim for high humidity, ideally 60–80%, to mimic its native understory environment. Use a humidifier, place a tray of water with pebbles nearby, or mist the air around the plant (avoiding leaves) to maintain moisture levels, especially in dry indoor settings.
- Watering: Keep the soil consistently moist but not waterlogged. Water when the top inch of soil feels dry, using room-temperature, distilled, or rainwater to prevent mineral buildup. Ensure excellent drainage to avoid root rot, as Calatheas are prone to overwatering issues.
- Soil: Use a well-draining, peat-based potting mix with perlite or bark for aeration. A mix designed for tropical plants or one with peat moss, compost, and perlite supports the rhizomatous root system, balancing moisture retention and drainage.
- Potting: Choose pots with drainage holes to prevent water accumulation. Select wide, shallow containers to accommodate the clumping, rhizomatous growth. Repot every 1–2 years or when root-bound to refresh soil and encourage healthy development.
- Fertilization: Feed every 4–6 weeks during the growing season (spring and summer) with a balanced, water-soluble fertilizer (e.g., 10-10-10) diluted to half strength. Avoid over-fertilizing, which can cause leaf tip burn, and stop feeding in fall and winter.
- Pruning: Remove yellowing, damaged, or dead leaves to maintain appearance and prevent disease. Trim at the base of the stem to encourage new growth. Since flowers are insignificant, remove them to focus energy on foliage development.
- Propagation: Propagate via rhizome division during repotting in spring. Separate healthy rhizome sections with roots and leaves, plant in moist soil, and keep in a warm, humid environment. New plants typically establish within 4–8 weeks.
- Pest Control: Monitor for pests like spider mites, aphids, or mealybugs, which can target the vibrant leaves. Treat with insecticidal soap or neem oil and improve air circulation to deter infestations, especially in high-humidity conditions.
- Disease Prevention: Prevent fungal issues like leaf spot or root rot by keeping foliage dry, avoiding overhead watering, and ensuring good air circulation. Remove affected leaves promptly and apply a fungicide if necessary to control outbreaks.
- USDA Zones and Environment: Grow as a perennial in USDA Zones 10–11 in frost-free, shaded areas with mild temperatures. In zones 9 and below, cultivate indoors or in greenhouses to protect from cold, maintaining high humidity and stable conditions.
- Seasonal Care: Increase watering and humidity in spring and summer to support active growth. In fall and winter, reduce watering slightly as growth slows, ensuring the soil remains lightly moist. Monitor indoor light levels, supplementing with grow lights if needed during shorter days.