Last Updated on October 2, 2022 by Plant Mom Care
Aspidistra elatior or cast iron plant, indigenous to Taiwan and Kuroshima, Uji and Suwanosejima islands of south Japan, is a perennial flowering plant species of the Asparagaceae family.
It’s an evergreen rhizomatous plant growing almost 3 feet tall and wide, with dark green glossy leaves 12–20 inches long. Under good conditions, the leaves can grow almost two feet wide after several years and can live as long as 50 years old. It produces maroon and cream-colored fleshy flowers of 8 lobes in early summer that are pollinated mainly by fungus gnats, according to a 2018 study.
It is well-known for tolerating neglect, giving rise to its name “cast iron plant”. It tolerates lows of light, humidity, temperatures, and even irregular watering. While is usually grown indoors, it can also be successfully grown outdoors in shaded areas of temperate climates.
There are several types of plant, each having its unique characteristics:
Aspidistra elatior Asahi, “Asahi” means morning sun in Japanese. This variety’s leaves open dark brown, turning green from the base with bright white splashes on its leaves as it matures.
Aspidistra elatior Variegata, is a variety that has variegated leaves of vertical white or yellow stripes.
Aspidistra elatior Lennon’s Song is a variety that develops long vertical bright white streaks on its long narrow ends to the leaves and a central stripe of pale green,
Aspidistra elatior Hoshi Zora, “Hoshi Zora” means starry sky in Japanese This variety is named due to its attractive white dot speckled leaves.
Aspidistra elatior Okame, is a variety that is very rare and hard to find. Like some of the other varieties, its large leaves have white streaks across them.
Aspidistra elatior Goldfeather, this variety grows rapidly (unlike the others) and enjoys cold weather.
Cast Iron Plant Light Requirements
This plant can deal with any lighting conditions except direct sunlight as its big lovely leaves can get sunburned and bleached. Indirect sunshine is the best for it, but it will thrive in a shaded or dim-lit environment too, so you don’t have to be concerned about the plant dying. Growth might slow down, but you won’t notice the difference since it’s a slow grower.
Cast Iron Plant Watering
This plant generally doesn’t need frequent watering since it is a slow grower. However, it should be watered when the soil is fully dry. Younger plants need watering more frequently than older ones – keep the soil damp but not soaking as water-logging can be fatal.
Well-drained soil is necessary for ideal growth and to stop root rot. Watering frequency should also be reduced in winter as well as if the plant grows in low-light conditions.
Cast Iron Plant Humidity
While this plant prefers high humid conditions, it’s not a big factor in their growth. Humidity in an average home is more than enough for it. Regular misting will help increase levels if your home is too dry.
Cast Iron Plant Temperature
This plant can deal with a varied range of temperatures, from 45-80°F, and can generally deal with lows of 23 °F, although it can kill off by frosty lows of 23-14 °F or below. This makes it a great plant to be grown outdoors as well in temperate climates. The plant might drop a few leaves in low temperatures but it will recover if not exposed for long periods.
Cast Iron Plant Soil
This is the most important area to focus on, even if it easily handles issues with light, temperature, and humidity. It requires well-draining soil to prevent it from water-logging and root rot. A good soil recipe includes a combination of clay and sand in equal parts.
It also needs a soil pH level of around 5.5/6.5 for ideal care.
Cast Iron Plant Repotting
Since the plant grows slowly, re-potting isn’t going to be a big part in caring for it. It only needs repotting every 3 – 4 years when it’s mature, while immature plants should be repotted every 2 years. Frequent repotting is detrimental for the plant as the roots are sensitive and don’t like to be handled often.
As is standard with most plants, move the plant to a pot that’s one size larger, being extra careful with handling the roots. Since this plant likes to be slightly root-bound, too much space can stress the roots.
Cast Iron Plant Propagation
The plant should be propagated (preferably in spring) as it’s easier to separate a stem and a root mass. Prepare two pots with well-drained soil and plenty of drainage holes. One pot should be slightly larger from the original plant and the other for the new plant.
Carefully remove the original plant from its home and remove excess soil from the roots without damaging the roots. Separate a bunch of roots having at least two stems with at least two leaves attached. Transplant the original plant into the pot you prepared for it (the larger one) and plant the new clump into the second one, making sure the clump is buried in the soil and the stem is standing straight.
Take care of the new plant like the original. Since it is such a slow grower, it will take around a year for any progress to be seen.
Additional Care
It only needs fertilizing once in 3 weeks during its growing period (April – October). Don’t fertilize the plant after repotting for at least a year. Any kind of fertilizer will work for this plant although a liquid fertilizer will help the plant thrive better.
Never feed the plant if it hasn’t been watered as it will damage the plant’s roots. Don’t be worried if the plant doesn’t appear to be growing and don’t add more fertilizer than necessary – it is a slow grower and fertilizing it will not make it grow faster.
Pruning this plant isn’t necessary since it grows so slow. The only time it needs pruning is when it has diseased or dead leaves to be removed.
Cast Iron Plant Common Problems
The plant is not seriously affected by pests, but mealybugs, scale, and spider mites might cause sporadic problems. One sign of pest infestation is leaves turning yellow and curling.
Rubbing alcohol, insecticidal soap, and neem oil will help get rid of these infestations, frequently repeating the process until pests are no longer seen. Trim any affected leaves to prevent eggs from hatching out again.
Scorched leaves are because of the plant getting exposed to direct sunlight for long periods. Remember, this plant can thrive in the shade without problems so adjust its location accordingly.
Yellow leaf is a symptom of over-watering, Immediate action must be taken to prevent all the roots from rotting away and killing the plant. Let the plant dry out for about 2 weeks before watering it again. Depending on the damage, wait for some time before considering repotting it into fresh, well-draining soil.
If leaf tips are becoming brown, it means that it is under-watered. While it is a hardy plant, it still has to be watered to thrive.
Brown spots appearing on the leaves is an indication that it’s infected by fungus. Cut away contaminated leaves and treat the plant using a spray of water and baking soda.
