Cast-Iron Plant Guide: How to Grow Cast-Iron Plants

The cast-iron plant (Aspidistra elatior) is a hardy flowering plant with glossy, dark green leaves. Cast-iron plants are also known as bar-room plants because they don’t need direct sunlight. These durable plants have green leaves of a striking deep shade, and come the summer growing season, outdoor cast-iron plants bloom milky white flowers with a mauve coloring on the inner surface. Aspidistra elatior are native to Japan and Taiwan and are common evergreen house plants because they thrive with low light and minimal care.

There are several cultivars of cast-iron plants, including:

1. 1. 'Lennon’s song': Named for Robin Lennon, an American grower of cut foliage plants, 'Lennon’s song' has green and yellow stripes on the leaves.
2. 2. 'Milky way': The 'Milky Way' cast-iron plant gets its cosmic name from the small, white star-like spots dotting the plant’s green leaves.
3. 3. 'Asahi': “Asahi'' is Japanese for “morning sun.” This cultivar has white tips at the end of its green leaves.
4. 4. ‘Okame': This variety has variegated dark green leaves with white stripes.

As an outdoor perennial, cast-iron plants can grow in USDA Hardiness Zones 6 through 11. Climates like northern California or the southern United States are ideal for cast-iron plants, which grow best in daily temperatures between 60 and 75 degrees Fahrenheit. Hardy to almost everything else, cast-iron plants don’t fare well in the cold. Temperatures below 50 degrees can kill them.

If you live in a cooler region, consider growing Aspidistra elatior as an indoor plant. Once indoors and in a temperature-controlled environment, these houseplants need relatively little care. Water them once a week; they have some drought tolerance but grow best with moderate amounts of soil moisture.

Cast-iron plants don’t need much beyond partial to deep shade, well-draining soil, and weekly precipitation. Follow these tips to keep your cast-iron plants healthy:

• Plant in slightly acidic soil. Indoor cast-iron plants grow best in neutral to slightly acidic soil. Outdoors, cast-iron plants can grow in clay and loamy soil.
• Give your cast-iron plants space to grow. Plant cast-iron plants at least one foot apart in your garden. For indoor plants, select a pot that is a few inches wider than the root ball, so there’s room to grow, and make sure the pot has plenty of drainage holes.
• Place your cast-iron plant in space with indirect light. Make sure your plant is in a shady area that receives indirect sunlight. Direct sun will bleach and damage its rich leaves.
• Water your plant once a week. Ensure the soil is dry between waterings. Overwatering can lead to root rot and may cause the plant to perish.
• Prune your cast-iron plant. Prune dead leaves to encourage new growth.
• Fertilize your plant in the springtime. Fertilize your cast-iron plant once a month in the spring with a liquid fertilizer to stimulate growth. Be careful not to damage the roots.
• Repot your plant every few years. Cast-iron plants are slow growers—you might only need to repot every couple of years. You’ll know it’s time to repot when you start to see roots emerging out of the soil. Be sure to add fresh potting soil with each new repotting.

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