The ninebark shrub (Physocarpus opulifolius) is a deciduous shrub native to North America. It is commonly grown in gardens and landscapes for its attractive foliage, showy flowers, and interesting bark. The shrub typically grows to a height of 5-8 feet and has a spread of 4-6 feet. However there are some dwarf cultivars available that stay smaller. The leaves of the ninebark are deeply lobed and serrated, with a dark green color that turns to shades of yellow, orange, and red in the fall. The flowers are small and white or pink, and they are borne in clusters that can be up to 3 inches across. The bark of the ninebark is also interesting, with a peeling texture that reveals layers of reddish-brown, tan, and gray.
The ninebark is a relatively low-maintenance shrub that can tolerate a wide range of growing conditions. It prefers full sun to partial shade and well-drained soil, but it can also tolerate drought and poor soil. Pruning is generally not necessary, but the shrub can be trimmed back in early spring to promote bushier growth and to remove any dead or damaged branches.
- Family: Rosaceae
- Native Range: Central and eastern North America
- Hardiness Zone: 2 to 8, however it struggles in the hot and humid summer climates of the deep South.
- Height: 5 to 8 feet
- Spread: 4 to 6 feet
- Bloom Time: May to June
- Bloom Description: White or pink
- Sun: Full sun to partial shade
- Water: Dry to medium
- Maintenance: Medium
- Suggested Use: Hedge
- Tolerates: Drought, Erosion, Clay Soil, Dry Soil, Wet Soil, Shallow-Rocky Soil, Black Walnut
How to Water a Ninebark Shrub
- Water with a garden hose or a watering can.
- Water the tree deeply when you see the soil has dried out.
- Additionally, water the tree slowly and evenly all around the root zone.
- In fact, avoid splashing the leaves with water, as this can cause fungal diseases.
- Let the soil dry out between waterings.
- Mulch around the base of the tree in order to help retain moisture and reduce weed growth.
- Lastly, provide supplemental water during periods of drought or dry weather.
Planting Ninebark Shrub
- Planting: Ninebark shrubs prefer well-drained soil and full sun to partial shade. They are relatively drought-tolerant once established, but will benefit from regular watering during their first growing season.
Pruning Ninebark Shrub
- Pruning: Ninebark shrubs benefit from regular pruning to maintain their shape and promote healthy growth. Prune in late winter or early spring before new growth begins, removing any damaged or dead branches and thinning out any crossing or crowded branches. You can also prune for size or shape as desired.
Caring for Ninebark Shrub
- Fertilizing: Ninebark shrubs generally do not require fertilizer. However if you would like, you can use a slow-release, balanced fertilizer in the early spring to promote healthy growth.
- Mulching: Applying a 2-3 inch layer of mulch around the base of the shrub can help retain moisture in the soil and suppress weed growth. Avoid piling mulch against the base of the plant, as this can lead to stem rot.
- Pests and diseases: Ninebark shrubs are relatively disease-resistant, but can be susceptible to powdery mildew in humid conditions. You can prevent this by providing good air circulation and avoiding overhead watering. The shrubs may also be prone to aphid infestations, which you can treat with insecticidal soap or neem oil.