The cast iron plant (Aspidistra elatior) is one tough plant, as its common name implies. It can grow in deep shade, is deer resistant, and can withstand drought. If that wasn’t enough, it can also be grown indoors as a houseplant in low light.
Native to Asia, the cast iron plant is an evergreen perennial. It spreads slowly via rhizomes. The sword-shaped leaves grow upright to 2 to 3 feet tall. It is known for its foliage rather than its flowers, as the star-shaped flowers are hard to see at the base of the plant.
The cast iron plant is hardy in USDA planting zones 7 to 11. Plant it in dappled to full shade. If it receives too much sun, the leaves will scorch. It is not picky when it comes to soil type and will thrive in sandy, loamy, and clayey soils. However, it does not like wet soil. It can grow under trees in dry shade. It can withstand periods of drought but will benefit from occasional watering. Cast iron plants can be fertilized with a slow-release fertilizer like Plant-tone® or Osmocote® when needed.
Cut the leaves back to the ground one by one when they look weathered, or cut back the whole clump every 2 to 3 years in late winter. The foliage will emerge again in spring. Divide plants when they are actively growing, in spring and early summer. Be sure the divisions have two or more leaves.
To grow a cast iron plant as a houseplant, plant it in a well-drained potting mix. Place it in a north-facing window or a low-light area away from south-facing windows. Water the plants when the soil is dry down 2 to 3 inches, allowing the water to drain from the pot. Do not leave water in the saucer. Fertilize indoor plants in the spring and summer with an all-purpose houseplant fertilizer. Monitor the leaves weekly for insects such as mites and scale.
For more information on shade plants, see HGIC 1716, Plants for Shade.