The cast-iron plant (Aspidistra elatior) has earned its reputation as a nearly indestructible houseplant, along with a beautiful outdoor foliage plant within its growing zones. This plant can survive lots of neglect and growing conditions that will kill many other plants, such as substantial shade. It has arching, lance-shaped, deep green, glossy leaves that can reach around 2 feet long and 4 inches wide. When grown outdoors, it produces creamy purple flowers near the base of the plant, but the blossoms usually do not appear with indoor plants. The cast-iron plant has a fairly slow growth rate, and spring is generally the best time to plant it.
|Botanical Name||Aspidistra elatior|
|Common Names||Cast iron plant, bar room plant|
|Plant Type||Perennial, herbaceous|
|Mature Size||2–3 ft. tall, 1–2 ft. wide|
|Sun Exposure||Partial, shade|
|Soil pH||Acidic, neutral|
|Bloom Time||Spring, summer|
|Flower Color||Cream with maroon on inner surface|
|Hardiness Zones||8–10 (USDA)|
Cast-Iron Plant Care
For a gardener with a brown thumb, this sturdy, long-lasting plant can be used in areas where all else fails. It is always green and can handle deep shade under deck stairs or along foundations that receive almost no sunlight. Plus, insects usually leave it alone, and it very rarely is bothered by disease.
Cast-iron plants require very simple maintenance: watering when the soil dries out and fertilizing for part of the year. Most mistakes that occur with these plants involve overwatering (they dislike waterlogged soil) or placing them in direct sunlight. With cast-iron plants, a fairly hands-off approach is typically best.
Watch Now: How to Grow Cast-Iron Plants (Aspidistra)
Keep cast-iron plants away from direct sunlight, which can bleach and burn the leaves. If you're keeping one as a houseplant, a north-facing window is ideal. Set it slightly back from windows that get strong light to avoid direct sun. When growing cast-iron plants outdoors, place them in a shady area with indirect sunlight.
Cast-iron plants tolerate a wide range of soils, as long as they have good drainage. They prefer organically rich soil with a slightly acidic to neutral soil pH. Outdoors, they can grow in sandy, loamy, and even clay soils. For container plants, simply use a standard quality potting mix.
While these plants have some drought tolerance, they like a moderate amount of soil moisture. Water young cast-iron plants regularly to keep the soil lightly moist but not soggy. Soil that remains wet for too long can cause root rot. Water established plants deeply, and then let the soil dry out a few inches down before watering again. A good general rule is to water when you can stick your finger in the soil and not feel any dampness.
Temperature and Humidity
Cast-iron plants prefer temperatures between 60 and 75 degrees Fahrenheit. They are not hardy to cold, and temperatures that drop below 50 degrees Fahrenheit can damage or kill them. So if you're growing your plant in a container outdoors, be sure to take it inside well before the threat of frost. Moreover, cast-iron plants like a moderate humidity level, but it's not a necessity for healthy growth.
Feed your cast-iron plant once a month with an all-purpose liquid fertilizer during the spring and summer months, or use a slow-release fertilizer in the spring. It's not necessary to fertilize during the fall and winter months. Only apply fertilizer after watering the plant to avoid burning the roots.
Cast-Iron Plant Varieties
There are several varieties of cast-iron plants, including:
- 'Variegata': This cultivar features green leaves with white stripes.
- 'Asahi': This variety's green leaves develop white tips as they grow.
- 'Hoshi-zora': This plant's name translates to starry sky, and its green leaves are speckled with yellow to white dots.
- 'Lennon's Song': The leaves on this variety have light green or yellow stripes.
Propagating Cast-Iron Plants
Cast-iron plants can be propagated by division. To start a new plant, take a piece of the rhizome (underground stem) that includes at least two leaves. Plant this piece either in a pot with fresh potting mix or directly in the ground. Keep the soil lightly moist, but ensure that it has good drainage. Also, make sure the new plant stays warm but isn't in direct sunlight. Once you see new shoots develop, you'll know your new cast-iron plant has developed its root system and its hardiness. Then, you can begin to treat it like an established plant.
Potting and Repotting Cast-Iron Plants
When growing cast-iron plants in containers, it's key to use a pot with ample drainage holes. Select a pot that's just slightly larger than the root ball to start, as these slow-growing plants won't outgrow their containers quickly. Once you see roots growing out of the soil, you'll know it's time to repot your cast-iron plant into something slightly larger. This might not happen for three to five years. Ideally try to repot in the springtime, and select one container size up. Gently remove your plant from its old pot, and place it at the same depth in the new pot with fresh potting mix.