Japanese barberry (Berberis thunbergii) is a hardy deciduous shrub, meaning it drops its leaves at the end of the growing season. It's commonly grown as a landscape plant even given its invasive nature.
These shrubs have a rounded growth habit and mature at around 5 feet tall and wide. They sport green leaves, along with pale yellow flowers that bloom in mid-spring. The leaves turn to shades of red, orange, purple, and yellow in the fall. They also have sharp thorns and red, oblong berries that last well into the colder months and thus are valued for the winter interest they provide. The shrubs have a slow to average growth rate, gaining around 1 to 2 feet per year. They're best planted in the fall, late winter, or after flowering in the spring.
|Botanical Name||Berberis thunbergii|
|Common Name||Japanese barberry, Thunberg's barberry|
|Plant Type||Deciduous shrub|
|Mature Size||3 to 6 ft. high, 4 to 7 ft. wide|
|Sun Exposure||Full sun|
|Soil Type||Average, dry to medium moisture, well-draining|
|Soil pH||6 to 7.5|
|Flower Color||Light yellow|
|Hardiness Zones||4 to 8 (USDA)|
|Toxicity||Mildly toxic to humans and animals|
Watch Now: How to Grow and Care for Japanese Barberry
Japanese Barberry Care
Barberry shrubs are often used for hedges, as their sharp thorns help to create a "living fence." When planted about 3 feet apart, the shrubs fill in the gaps quickly, forming a wall of foliage. Barberry shrubs are also effective for erosion control and are among the most deer-resistant shrubs. Overall, they have few pest or disease problems.
The care for Japanese barberry is minimal, as the plant can thrive in various growing conditions. It even can tolerate urban conditions. Typically the most work you'll have to do for this shrub is keeping it pruned, but even that's minimal unless you are particular about its shape or size.
The Japanese barberry is considered an invasive species in parts of North America due to its tolerance for many growing conditions and ability to outcompete native plants.
This shrub readily grows in average soil. It can tolerate a range of soil conditions, as long as there is good drainage. Soggy soil can cause root rot.
Japanese barberry has good drought tolerance, so you’ll likely only need to water your shrub during prolonged dry periods. If the plant’s leaves are wilting or falling off during the growing season, that’s a common sign it could use some water. Moreover, give a new shrub regular watering to maintain slight moisture in the soil during its first growing season.
Temperature and Humidity
Japanese barberry can adapt to many climate conditions and does well throughout USDA growing zones 4 to 8. It has good cold tolerance but prefers to be sheltered from strong winds. Plus, it can struggle in very hot and humid conditions.
Fertilizing Japanese barberry is generally not necessary unless you have very poor soil. To boost plant health and vigor, you can fertilize your barberry in the late winter or early spring before flowering begins with a slow-release shrub fertilizer.
Is Japanese Barberry Toxic?
The Japanese barberry shrub is mildly toxic to humans and animals, but the berries are so sour-tasting that it's hard to indulge. The shrub needs another type of warning, however. The plant is believed to be a preferred habitat for Lyme disease-carrying black-legged ticks, as well as white-footed mice on which ticks feed.
Japanese Barberry Varieties
There are several cultivars of Japanese barberry that vary in size, shape, and appearance. Some have an upright and rounded growth habit while others tend to spread out or remain rather small. Plus, some shrubs feature striking foliage colors besides the typical green. Popular varieties include:
- 'Crimson Pygmy': True to its name on both counts, this variety bears reddish-purple foliage and remains compact. It usually reaches around 2 to 3 feet tall and wide.
- 'Aurea': This plant also remains rather short, topping out at 3 to 4 feet tall and slightly wider. It is known for its vibrant yellow foliage.
- 'Rose Glow': This variety reaches around 5 feet tall and 4 feet wide. And its claim to fame is the fact that its leaves have three colors: a rosy red that's mottled with pink and white.
- 'Concorde': This compact, rounded shrub only reaches around 2 feet tall and wide. It features deep purple foliage that becomes even more vivid in the fall.
Pruning generally isn’t essential for Japanese barberry shrubs. If you wish, you can leave them alone and only prune off dead, damaged, or diseased portions as needed. Or you can prune to obtain a specific shape or size, such as pruning to create a hedge. This more extensive pruning should take place after the shrub flowers in the spring or the early summer. Avoid pruning within two months of your projected first frost date in the fall (unless you’re removing damaged portions), as this can leave the shrub vulnerable to injury or disease.
Whenever you're working with a Japanese barberry shrub, be sure to wear gloves to protect yourself from the plant's extremely sharp thorns.
Propagating Japanese Barberry
It's easy to propagate Japanese barberry with cuttings, the preferred method over the more challenging way of growing from seeds. Take cuttings in the spring after flowers have faded. You can also take semi-hardwood cuttings in the summer.
- Cut a 6-inch length of growth from the tip of a branch, cut below the leaf node.
- Remove shoots and leaves on the bottom of cutting but leave the greenery on the top half.
- Dip the shoot and any of its nodes in rooting hormone to promote growth.
- Fill a pot with coarse sand that is drenched with water and let it drain.
- Once drained, put the end of the cutting with the rooting hormone into the wet sand, but let the leaves stay above the sand.
- Mist the cutting with water.
- Cover the pot with a plastic bag to keep the cutting moist.
- If the soil dries, add a bit of water, but not too much.
- Roots should appear within 21 days; tug on the plant to see if you feel any resistance from rooting.
- Transfer the cutting into a larger container with potting soil, continue to water.
- In the fall, plant your Japanese barberry shoot.
Common Pests & Diseases
Japanese barberry shrubs are susceptible to scale insects and aphids which will suck on the plant's juices. Dislodge large infestations of aphids with a high-pressure garden hose spray.
Diseases that can afflict the plant include powdery mildew, verticillium wilt, anthracnose, and bacterial leaf spots. Use fungicides for most problems, but the wilt may be irreversible and cause the shrub to die.
Barash, Cathy Wilkinson. Prairie & Plains States Getting Started Garden Guide: Grow the Best Flowers, Shrubs, Trees, Vines & Groundcovers. Cool Springs Press, 2015