Mahonia Cultivation and Care: A Comprehensive Guide

The foliage of most mahonias is large and eye-catching. The leaves of mahonia look similar to holly leaves with teeth. Mahonia is also known as holly-leaved shrubs, since they belong to the barberry family and look similar to holly. Mahonias are great for shady areas in your yard, and they are also popular privacy hedges. They are often used for minimalist landscapes, particularly in the south, because of their dramatic, architectural appearance.

Mahonias, native North American woodland plants with a tropical appearance, are easy to grow. The majority of floral sprays in early spring or late winter are golden-yellow and fragrant, attracting pollinators such as bees and butterflys. Birds may also seek refuge in the thick green foliage. The berries are dark blue-black and attract a variety of birds. These upright evergreen shrubs are attractive because they provide year-round interest and their spiky leaves repel deer. Mahonias can be planted in the spring or fall, when temperatures are mild.
Mahonia is the same as Oregon Grape.
Oregon grape (Mahonia) is a mahonia species. There are over 70 mahonia species, all of which belong to the barberry family. The flowers attract pollinators, and the berries are a favorite among birds and mammals. The dense foliage is a good cover for small animals.

Botanical NameMahonia spp.
FamilyBerberidaceae
Plant TypeShrub
Mature Size: 3-10 ft.
Sun ExposurePartial
Soil TypeMoist, Well-dained
Soil pHAcidic, neutral, alkaline
Bloom Time Autumn, winter, Spring
Flower Color Yellow and red
Hardiness Zones 5-9 of the United States Department of Agriculture
Native Area North America and Asia
Mahonia Care
Mahonias have a reputation for being slow-growing shrubs that are hardy and require little maintenance. It is important to choose the right site for them, as they don’t like being moved. You should protect your shrubs from freezing winds that can damage the plants in winter. Also, give them enough room to grow as they don’t like being crowded.

Mahonia shrub with small yellow flowers clusters and long branches
Mahonia branch with tiny yellow flowers and bud cluster in closeup
Mahonia branch with yellow-green flower buds and waxy leaves
Mahonia shrub branch with pointed leaves and yellow flower clusters
Mahonia shrub with bright pink branches and blue berries close-up
Light
Some mahonia thrive in heavy shade, while others can tolerate the full sun. Some species can grow leggy in deep shade.

Soil
The mahonias are not particular about what type of soil to grow in. They do well with sand, loamy and clay soil types, as well as different pH levels. It is enough that the soil be moist, and drains well.

Water
Mahonias are best watered regularly and deeply during their first year of establishment (especially). However, you should avoid overwatering. Once established, mahonias are drought-tolerant, and only require watering during hot, dry periods.

Temperature and Humidity
Mahonias can tolerate a range of temperatures, except for the risk of frost-bite. They can usually tolerate temperatures as low at 5 degrees Fahrenheit. Mulching the roots in the fall could be helpful if the temperatures are this low.

Fertilizer
The plants do not require a strict fertilization regime. A rich layer of compost or mulch with fish and bones meal or a slow-release low-nitrogen fertilizer applied in the spring should suffice.

Mahonia Types
Mahonia is a genus that contains 70 species, plus hybrids and cultivars. Popular and readily available varieties are:

Oregon grape (Mahonia): Also known as Berberis aquifolium, it grows to about 6 feet high and is hardy from USDA zones 5 through 8.
‘Marvel Mahonia’: upright growth habit, large fronds, fragrant sprays in the late fall or early Winter; clusters in the summer or fall of black berries.
Mahonia repens (Creeping Mahonia): A low-growing shrub that reaches around one foot in height; it is a good ground cover with its leaves and hardy from USDA zones 5 through 8.
Fremont’s mahonia, (Mahonia fremontii), reaches up to 8 feet in height; hardy USDA zone 5.
Mahonia x Media ‘Charity: Tall, tough and adaptable hybrid. Can reach 15 feet high; used often to create a privacy fence. Hardy in USDA zones 7-9.
WARNING
Leatherleaf mahonia, or Mahonia bealei, was once a popular ornamental plant. However, it has now been classified as highly invasive by many southern states.

Pruning
Mahonias do not have a demanding pruning regime. Light pruning can be done every few years, in the early spring after frost has passed. This will encourage healthy growth of foliage. Thinning out overcrowded branches can help maintain a neat appearance.

Cutting it to the ground will help your shrub recover a compact and full habit. It’s best to mulch the shrub base after this and give it a light feeding to encourage healthy new growth.

You should also control suckers which sprout from the slow-growing mahonia. If you do not want your space to be overrun with mahonias, it is best to remove them.

Propagating Mahonia
Cuttings of most mahonia species can be propagated easily by cuttings that are taken before the flowering season in late summer or early autumn. The following steps can increase your chances of success.

Choose a semi-ripe growth of the current season and cut it to a length of 6 inches.
Remove the leaves at the bottom of the cutting.
Dip the cut ends in rooting hormone.
Plants should be potted in a moist, well drained soil.
Place in a warm place in the greenhouse or indoors.
Cover the plastic with a sheet to keep out moisture.
Keep the soil moist until the roots have taken hold.
Mahonia Seeds: How to Grow Mahonia
Follow the steps below to try and grow mahonia seeds in spring:

Remove the seeds and fleshy berries
Cold stratify all seeds for at least one month
The seeds should be moved to a warm location (around 65-70 degrees Fahrenheit). Leave them there for another month.
Plant the seeds about 1/4 inch deep in the potting soil
You can also sow seeds directly into the ground during the fall, and hope for spring germination.

Mahonia Repotting and Potting
Mahonia is not suited for growing in containers due to their tendency to spread. Grow it in the soil with enough space to allow it to spread.

Common Plant Diseases
Mahonias have a robust nature; serious diseases and pests are not common. Sometimes they can suffer from rust, powdery mildew or brown spots on their foliage. Although neither of these is usually fatal, it can cause leaves to curl, wither, or drop.

These problems can be minimized by watering shrubs at their base, rather than on the leaves. Avoiding a moist location and removing the infected parts will also help. If the problem is hard to control, fungicides may be needed. Mahonia aquifolium has a high susceptibility to rust.

The FAQ
What plants are similar in appearance to mahonias?
Many mahonia species have leaves that are similar to holly, with serrated green leaves. Mahonia, unlike holly is a member of the barberry family. Barberries, on the other hand, are not toxic.

How fast do mahonias grow?
Mahonias grow slowly and steadily, depending on which species you choose.

Do mahonias prefer the sun or the shade?
Mahonia can tolerate full sun if it is well-watered. However, it thrives when in partial shade.


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