Oregon grape, also known as holly-leaved barberry, is the state flower of Oregon. This woody perennial shrub can grow up to six feet tall and makes an excellent plant for landscaping in a shade garden. It also makes a good hedgerow plant or border plant in a more naturalized setting.
The leaves closely resemble holly leaves, although they are unrelated to hollies. The fruits look like bunches of grapes, but they are not related to grapes. Despite its name and looks, this plant is a broadleaf evergreen member of the Berberidaceae family. It was previously known as Mahonia aquifolium but has been reclassified as Berberis aquifolium.
With pinnately compound leaves edged with sharp points, dense bunches of showy yellow flowers, and clusters of purplish-blue fruits, this plant is a standout in all seasons. The leaves take on beautiful shades of red, bronze, or scarlet in the fall and winter. This plant provides year-round interest in the landscape and provides food and shelter for various wildlife.
If Oregon grape sounds interesting, keep reading to learn more about how and where to use it in your home landscape!
Plant Overview
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Natural History
Various cultivars come in different heights and leaf styles, serving ornamental purposes.
Oregon grape is native to northern North America, primarily in eastern and western Canadian provinces and the northwestern United States. Its natural habitat is found primarily in mountainous and hilly regions with cooler climates.
Plants develop upright, woody stems and will spread by underground rhizomes to form colonies. While they are somewhat slow-growing, a single plant will eventually sprout numerous stems within the immediate vicinity.
In the springtime, clustered bunches of bright yellow flowers bloom. The flowers are slightly fragrant and attract pollinators. After flowering, clusters of dark purple-blue fruits ripen in late summer and may persist into winter. These fruits attract birds and mammals. In the late fall and winter, the foliage turns a showy purplish-bronze.
Many cultivars are available with different growth habitats, varied heights, and ornamental leaves. Humans have also used these plants for purposes other than ornamental landscaping. The ripe berries are edible but very sour and can cause digestive upset if eaten raw. The cooked fruits can be used for jams and jellies. The fruits and bark have both been used to make dye.
Propagation
You can propagate by seed, cuttings, or division. Division is quicker and will yield a full-sized plant in less time than starting from seed. If you have more than one variety planted nearby, there’s no guarantee that your plants propagated from seed will be true to the parent type. Propagating by stem cuttings is also an easy and reliable method to grow more plants.
Seed
Grow seedlings in moist soil and indirect light until they’re several inches tall.
Seeds should be cold-stratified. To best replicate natural conditions, plant seeds outside in the fall and allow them to spend the winter where you would like them to grow. If you want to start plants under more controlled conditions, collect fruits in the fall, separate the seeds from the fruits, and place seeds in the freezer for approximately three months. Sow them in pots with moist soil in the spring and keep them warm but shaded until they germinate.
You will want to keep growing your seedlings in moist soil and indirect light until they are several inches tall. When they are large enough and strong enough, they can be transplanted outside into their permanent location. Be sure to keep your seedlings protected and moist because they will be quite sensitive until they have become well-established outdoors.
Division
Carefully cut the stolon from the parent plant using sharp pruners to propagate a new stem.
Oregon grape spreads readily by stolons. When one of these stolons begins to send up a new stem, you can use sharp pruners to separate the stolon from the parent plant. Dig around the new sprout to remove and preserve as much of the root as possible. Then, transplant it directly into a new location. Be sure to water this freshly separated plant well for at least the first week after transplanting to help it recover.
Cuttings
Ensure the soil remains damp and place the cutting in a warm, shaded spot.
To propagate from cuttings, take a couple of stem cuttings of fresh spring growth, each approximately four inches long. Remove any lower leaves along the stem so you have a bare stem with some young leaves at the top. Dip the lower 2 inches of stem in a rooting hormone and immediately plant it in fresh, clean potting soil.
Keep your cutting in a warm, shaded place, and keep the soil consistently moist. New roots should begin to form in a few weeks, but not every cutting will root successfully. When you see your little cutting start to sprout new growth, that’s a good sign that it has started to grow its roots and will develop into a new plant. Keep it potted and moist for a little longer before transplanting it into your shade garden.
Planting
The ideal times for transplanting are early spring or fall on a cool, overcast day.
If you choose your plant from a nursery, look for a variety appealing to you, and choose a healthy-looking plant. A healthy plant appears fresh, green, and vigorous. There should not be any signs of rot, disease, or browned leaves. If you can’t transplant your new Oregon grape right away, it’s okay to leave it in the nursery pot for a while; keep it in a shaded location and try to keep the soil moist.
The best time for planting and transplanting will be in the early spring or during the fall. Choose a cool, overcast day for your gardening task. Grab some sturdy gardening gloves and prepare a hole for your transplant where you ultimately want it to grow.
Dig a hole slightly larger than the rootball of your plant. Carefully remove the plant from its pot and place it in the hole. Fill in around the edges with fresh soil to fill in any gaps. Then, water it well and keep it moist for at least the first week or two to help it adjust to its new home.
How to Grow
Follow the guidelines below to help you choose an ideal location. Once your plant starts growing, you’ll have some minimal annual maintenance, primarily pruning and weeding. Otherwise, this should be a fairly trouble-free plant to enjoy in your garden!
Sunlight
It is best to avoid full sun to prevent leaf discoloration and burning.
Oregon grape will do best in partial to full shade. Avoid planting it in full sun as this can cause the leaves to bleach and burn. This plant tolerates full, deep shade but displays the best flowering and fruiting with a couple of hours of dappled sunlight daily.
Water
Once established, this plant becomes highly tolerant to drought.
Offer a location with medium-moisture soil. Oregon grape is a great addition to a drought-tolerant garden once established in a suitable location.
Soil
This plant thrives in organically rich, well-drained soil with an acidic pH of 5.0 to 7.0.
Oregon grape loves organically rich, moist, well-drained soil. The soil should be acidic, with a pH between 5.0 and 7.0. The leaves will turn yellow if the soil is too alkaline.
Climate and Temperature
This flowering shrub tolerates freezing temperatures, thriving in zones 5-8.
This plant is hardy in USDA Plant Hardiness zones 5 through 8. It tolerates freezing temperatures but does not tolerate excessive summer heat.
Fertilizer
Add organic compost during planting or as an occasional boost every few years.
Because this plant is naturally well-adapted to conditions in the Northwest, you should not need to add any extra fertilizer if you are growing Oregon grape in its natural habitat. You can, however, give it a bit of organic compost when planting or as an additional boost every few years to enhance its performance in your yard.
Maintenance
Manage shape and size with occasional pruning and controlling of root suckers.
Oregon grape is a fairly low-maintenance plant. You can expect to do some regular pruning to remove any unwanted root suckers unless you want to allow them to naturalize and form dense stands.
As with any gardening project, keep your plot weeded to reduce competition from weeds and other possibly invasive species that might try to creep into your landscape.
Garden Design
This shrub enhances shady gardens with year-round interest in woodland or park-like settings.
Oregon grape is a welcome addition to your shade garden landscape. This is a great choice if you have a woodland garden plot with space for a spreading shrub. You can even grow it in a large container or durable raised bed. Container gardening can be beneficial for the more compact varieties.
To create a wildlife-friendly landscape, use it to attract birds and pollinators. Rabbits and deer generally leave it alone.
Pair it with plants that thrive in a shaded location with rich, moist soil. Be sure to leave plenty of space for each plant to grow and spread in its way. Don’t attempt to cultivate anything else too close to your young Oregon grape because it will need some extra space to broaden its form and develop into at least a small colonial growth.
Varieties
Berberis ‘Compacta’
This variety is characterized by its low, spreading growth.
‘Compacta,’ as the name implies, is a more compact variety. It grows two to three feet tall but can still spread to form more extensive colonies. It has showy yellow flowers and beautiful bronze winter foliage.
Berberis ‘King’s Ransom’
‘King’s Ransom’ reaches five feet, boasting yellow flowers, purple fruits, and distinctive foliage.
‘King’s Ransom’ is a cultivar that grows to about five feet tall. It has showy yellow flowers and purple fruits. The colorful leaves set this cultivar apart from the others. Foliage is bluish-green through most of the growing season, turning deep burgundy red in the fall and winter.
Berberis ‘Orange Flame’
“Orange Flame” maintains its small stature at two feet while sporting blue-black fruits and yellow blossoms.
‘Orange Flame’ is a cultivar that stays quite compact, growing to only two feet tall. Yellow flowers and bunches of blue-black fruits keep this plant interesting during most of the growing season. The foliage is shiny pale green with splashes of coppery orange during the growing season, changing to reddish-bronze during the fall and winter.
Creeping Oregon Grape, Mahonia repens
Mahonia repens, a low ground cover, reaches one foot tall and spreads three feet wide.
The creeping Oregon grape is a low-growing ground cover, staying only about one foot tall and spreading about three feet wide. This variety is a bit more sun tolerant but makes a great shade garden addition.
Berberis ‘Marvel’
‘Marvel’ is known for its bluish-black fall fruits and profuse yellow blooms.
‘Marvel’ is a cultivar that grows up to six feet tall and has dark green leaves. Multiple elongated flower spikes bloom with abundant bright yellow blossoms, followed by bluish-black fruits that linger on the plants well into the fall and winter months.
Pests and Diseases
Fortunately, this shrub is not bothered by many pests and diseases. This plant is quite hardy and low-maintenance, with relatively few problems. However, you may occasionally encounter issues with the foliage, and if you do, here are a few of the more common problems you may see.
Leaf Spot
Leaf spot causes brown spots on the foliage.
This bacterial or fungal infection causes brown, dead-looking spots to appear on the foliage. If leaf spot is mild, you won’t need to do anything, as your Oregon grape should not experience any long-lasting consequences. If you notice that a few of the leaves appear to be badly infected, you can prune these off and dispose of them to help prevent infection from spreading further.
Leaf Scorch
Avoid direct sunlight to prevent unsightly leaf scorch.
Oregon grapes do not like too much direct sunlight. Prolonged exposure to bright sunlight will cause leaf scorch on the foliage. The first sign of leaf scorch may be wilting. Leaves will then turn yellow, dry out, and become brown and dead. Leaf scorch is simple to prevent; don’t try to grow this plant in direct sunlight.
Rust
Prevent rust with strategic watering and careful leaf care.
Rust is a fungal disease spread by spores from one infected plant to another. Rust looks like rusty brown spots on the foliage. Advanced infections will also cause the stems, flowers, and fruits to appear rusty brown. Prevention is the best method to deal with rust. Buy healthy-looking nursery plants, avoid unnecessary watering from above, and destroy any infected leaves.
Frequently Asked Questions
Not all Oregon grape plants are the same, and some are considered invasive in certain areas. For example, the leatherleaf mahonia (Mahonia bealei), also known as Beal’s mahonia, is native to China and is considered an invasive species in the southeastern United States. The Oregon grape holly (Berberis aquifolium) is native to western North America and is not an invasive species.
If you are trying to grow from seed, it can take a few years. First, you’ll need to collect and cold-stratify the seeds. From the time the seeds sprout until the plant is mature enough to bloom can easily take another two years. If you buy a young nursery-grown plant from a greenhouse or garden center, you can expect it to bloom within one or two years after planting, depending on how large the plant is when you buy it and what season you plant it.
Oregon grape holly plants are not related to either grapes or hollies, but they do have a physical resemblance to both. Grapes are in the grape family (Vitaceae), and hollies are in the Aquifoliaceae family. This shrub is in the Barberry family (Berberidaceae), which includes various plant species, including trees, shrubs, and herbaceous perennials. While the fruits may look like grapes, they should not be eaten or grown like them. They are uniquely different plants.
Final Thoughts
Oregon grape holly is an interesting plant that is a terrific addition to shade garden habitat. If you can provide desirable environmental conditions, this plant is easy to grow and worthwhile. It is a native species that is ornamental, is beautiful throughout the year, and offers benefits to attract wildlife. You can use it in many shaded settings, including as a lush privacy hedge or hillside erosion control. The eye-catching flowers, foliage, and fruits are sure to please!
