Japanese aralia is a popular houseplant native to the southern Japanese islands, Korea, and Taiwan, where it grows in subtropical conditions. A hardy, upright plant, Japanese aralia can grow up to 16 feet tall outdoors, and about six feet tall indoors, growing at a rate of 8–12 inches a year. Its lush, dark green leaves and ease of care make it a very popular varietal for indoor plant collections, but it's also a staple of tropical gardens and arboretums.
|Botanica name||Fatsia japonica|
|Common name||Japanese aralia, Spider's web, Glossy-leaved paper plant, False castor oil|
|Mature size||4–5 ft. tall, 3–4 ft. wide|
|Sun exposure||Partial sun, shade|
|Soil type||Moist but well-drained|
|Hardiness zones||7 to 9 (USDA)|
Watch Now: How to Grow and Care for Japanese Aralia
Japanese Aralia Care
Japanese aralia boasts large, leathery leaves that can measure a full foot across. Under the right circumstances, mature specimens will produce groups of small white flowers each fall, followed by shiny black berries. Overall, Japanese aralia are fairly easy to care for, and they are popular houseplants due to their hardiness.
Japanese aralia grows best when places in partial to full shade. Exposure to bright, direct sunlight can bleach the plant's leaves, so only place it beneath diffused morning light, never harsh afternoon rays.
The hearty Japanese aralia plant is not too picky when it comes to soil. It prefers moist but well-drained soil (clay, chalk, and loam all work) that is neutral to slightly acidic.
Regular moisture is essential for the Japanese aralia during its growing season (spring and summer). Water regularly to ensure the soil never dries out, saturating the soil completely until water runs from the container's drainage holes. During the fall and winter months, cut back on your watering slightly to allow the plant to rest.
Temperature and Humidity
The Japanese aralia plant prefers cooler temperatures, doing best in rooms that are kept to a temperate 60–70 degrees Fahrenheit. It does not necessitate any additional forms of humidity to thrive within your home but should be kept away from particularly strong or cold drafts.
To give your plant an added boost of nutrients, feed it regularly with a weak liquid fertilizer throughout the growing season. Cut fertilizer back to once a month or so in the fall and winter.
Japanese Aralia Varieties
There are several varieties of Japanese aralia that enjoy popular favor as houseplants. They include:
- Anneise: Characterized by its vibrant colors, this varietal boasts rich emerald leaves spotted with sunny yellow.
- Moseri: Instead of tiny white flowers, the Moseri varietal has large blooms, as well as large black berries. It's also flowers during the winter months, showing off it's flowers from October to January.
- Spiders Web: This varietal gets its name from the unique, web-like speckles and veins that dot its leaves.
Propagating Japanese Aralia
This varietal can be propagated both by seed and stem-tip cutting. It's unlikely your plant will flower indoors, so you are better off opting for the stem-tip cutting method. To propagate, taking a cut of stem from a mature plant early in the growing season and use a rooting hormone for best success. Place in a pot filled with moist soil and cover the pot with a plastic bag. Keep cuttings in a warm, humid place until new growth emerges—it should take root in one to two months.
Potting and Repotting Japanese Aralia
Because Japanese aralia can grow to be so large, keeping an eye on it pot is important. Once the plant is showing signs of outgrowing its vessel (like roots growing out of the drainage holes), or at least once a year, replant your Japanese aralia in a larger pot.
Like many plants, Japanese aralia is susceptible to a variety of aphids, which are also known as plant lice. These very common pests feed on the leaves of the plant (typically new growth) and can stunt or hinder its ability to prosper. They're fairly easy to control if caught early enough and can be killed off using a neem oil spray. More notable is the Japanese aralia's issue with mealybugs, also known as white fuzzy bugs. Characterized by spots on the underside of the leaves that look like small splotches of cotton or powder, mealybugs leach fluids from the stems and leaves of the Japanese aralia, robbing it of the essential nutrients it needs to grow. Additionally, they excrete a sticky sap-like substance called honeydew onto the foliage, which can make the plant more susceptible to sooty mold. To rid your plant of mealybugs, rub the foliage down periodically with cotton swabs lightly coated with alcohol. For a serious infestation, treat your plant with a neem oil spray.