Favorite Oregon Grapes for Landscape and Garden

A well-established Oregon grape looks spectacular in full fruit.

It was not too many years ago that gardeners often thought of Oregon grape (Mahonia aquifolium, syn. Berberis aquifolium) as primarily a woodland plant that did not belong in the ornamental garden. This Pacific Northwest native, which is the state flower of Oregon, is a member of the barberry family. Whereas Oregon Grape does not have spines like barberry, the plants do have spiny leaves–one of the reasons home gardeners avoided them. But, times change, as do trends, whether with regard to plants, fashion, or whatever the commodity. As for mahonia, there has been a resurgence of it in gardens.

Mahonia Landscape Traits

Brilliant bursts of yellow flowers are the crowning glory or Oregon holly in spring. (Image by Mike Darcy)

Oregon grape’s evergreen leaves are deep green, compound (leaves with multiple leaflets), and sometimes turn red or bronzy shades in winter. The common name refers to the attractive clusters of grape-like blue berries that appear in the fall. While these berries are edible, they are not particularly tasty when eaten directly off the plant, but they are quite good in jams and jellies. They are also an excellent food source for wild birds.

Attractive flowers are another attribute that makes Oregon grape a desirable garden plant. Most forms have brilliant yellow flowers borne in rounded, dense, spiky clusters that provide a very bright spot of color in the garden. In the Pacific Northwest, these bloom in late winter. In other areas of the country with colder winters, they tend to bloom in spring. On the West Coast, the flowers are a valuable source of nectar for hummingbirds as well as bees.

Once established, Oregon grapes require little care and minimal supplemental water. Protect the shrubs from bright sunlight, whether in summer or winter, to prevent leaf sunscald. While I have never heard of them being referred to as invasive, they do spread by underground stems, and in some states where they are not native, they have naturalized into the wild.

Mahonia Varieties

The variety ‘Soft Caress’ has soft, palm-like foliage.

Different species and new cultivars on the market have different heights and textures, giving gardeners new design options. When visiting a garden center, you may be surprised by the many cultivars available. Those living in the Pacific Northwest have even more varieties from which to choose. Our many specialty nurseries carry species and cultivars that are not always easy to find elsewhere. Regarding the selections mentioned below, I have tried to maintain a list of plants readily available at local garden centers across the country.

Oregon grape (Mahonia aquifolium, USDA Hardiness Zones 5-8) is an evergreen woodland shrub found in coniferous forests and open woodlands from British Columbia down to northern California, primarily on the western side of the Cascade Mountains. Dark, evergreen leaves, which are spiny and holly-like, look beautiful year-round. The dense, bushy shrub can reach 6-12 feet in height. Clusters of tiny, bell-shaped flowers of bright yellow flower from late winter to spring. Bluish berries mature by fall and may persist into winter.

Charity Oregon grape (Mahonia x media ‘Charity’, Zones 6-9) is a hybrid that has become very popular with gardeners due to its more delicate evergreen leaves and extra-large, prolific sprays of yellow flowers. It is a tall plant, reaching 8-15 feet in height, so it needs plenty of space in the garden. It makes an excellent background plant in a shrub and perennial border.

Creeping Oregon grape (Mahonia repens, Zones 5-8) only reaches about 1-3 feet in height and makes a good woodland ground cover. It can take sun but also deep shade and is drought tolerant once established. It is native from the Pacific Northwest down to West Texas, so drought tolerance and bloom times vary. In the North, it tends to bloom in late winter, but further south if produces small, rounded, tight clusters of yellow flowers as late as early summer. Its deep green, holly-like foliage turns reddish hues in winter. It is an easy-care, low maintenance plant that is often overlooked as a ground cover.

Soft Caress Oregon grape (Mahonia ‘Soft Caress’, Zones 7-9) is a relatively new hybrid mahonia on the market, and, as the name implies, the almost palm-like, evergreen foliage is soft and thornless. The growth habit is such that it is compact enough to be planted in containers and also makes an excellent border plant. Its yellow flowers appear in late winter to early spring and dark blue fruits mature by fall. This mahonia needs extra shade and protection from high winds, so plant it in a sheltered spot away from the hot afternoon sun. It reaches a height of about 3 feet and requires little supplemental water once established. I have found that when gardeners are first introduced to ‘Soft Caress’, they are amazed to discover it is a mahonia.

Mahonia Care

The evergreen leaves of Oregon grape can turn shades of red and burgundy in the colder months.

All mahonias grow best in soils that are fertile, very well-drained, and slightly acidic. At planting time, fortify their soil with Black Gold Peat Moss, which is slightly acid and an excellent source of organic matter. Provide them with partial sun to shade for best growth, flowering, and fruit set. These are true forest shrubs that dislike harsh winds that will desiccate their foliage. All-day winter sunlight can also scorch the leaves, so plant them where they are shaded for at least part of the day.

Oregon grape was once relegated to native and woodland gardens but has now become a mainstream garden plant for many good reasons. It is easy to grow and has bright winter flowers that provide food for hummingbirds and bees at a time when few other plants are blooming. Moreover, once established, most forms require little supplemental water. Visit your local garden center to see its spectacular, leaves, berries, and flowers for yourself. You’ll want to buy one right away!

The blueish berries are edible when ripe but are better left to birds. (Image by Mike Darcy)

Western Riparian Trees for Wet Soils

Trees that naturally grow by waterways or riversides make good landscape trees for wet ground.

Do you have moist ground in your yard but want trees for the site? For a gardener with wet or damp soil, finding a tree that will thrive in such conditions can be challenging. When browsing through a garden center and reading the cultural requirement for many of the plants, probably one of the most common phrases will be “needs a location with good drainage”. Often when I give presentations to garden clubs, a very common question asked is what kind of trees are recommended for areas with wet soils.

When recommending trees for wet soils, I have tended to rely less on textbook comments and more on actual experience. While my own garden does not have this issue, I have visited many gardens with moisture problems. The following selection of trees for wet soils has been collected from talking with other gardeners and actually seeing these trees growing in yards and landscapes.

But, in general, trees adapted to wet soils tend to either be natural waterside trees or lowland trees that inhabit flood plains that become seasonally water saturated. These are called riparian trees, and they are worth seeking out when planning landscape plantings for damp ground. When planting these trees in the landscape, it is always wise to enrich the soil with a fertile amendment, like Black Gold® Garden Soil.

Trees for Wet Soils


The brilliant fall foliage of tupelo is one of its best features.

If I had to pick just one tree for an area with wet soil, it would be Nyssa sylvaticaCommonly called blackgum, sour gum, or Tupelo, it is a very hardy deciduous tree native to eastern North America, from southern Ontario to central Florida. Honey made from its flowers, appropriately called ‘Tupelo Honey’, is well known across the east, especially in northwest Florida. The trees are dioecious, meaning there are separate male and female trees that flower in late spring. Male trees have pollen-bearing flowers, while the female trees are fruit-bearing. Female trees develop small, bluish-black fruit if a male tree is close by for pollination. The olive-shaped fruits appear in small clusters, and while they can make a mess on a deck or driveway, birds like them.

The Tupelo is very well adapted to the Pacific Northwest and will reach a height of 35-50 feet. It is disease and insect resistant and makes an excellent shade tree.  However, the real attribute of the Tupelo is its spectacular fall color.  The simple leaves turn yellow and orange and then bright red before dropping. The red fall color is outstanding.


Alder naturally grow along watersides, right up to the edge!

Alder (Alnus spp.) is another group of trees that are moisture loving and fast growing. Red alder (Alnus rubra), is a riparian native from Alaska to northern California. It usually reaches about 50 feet and has attractive bark that is light gray. The dark green leaves are rust colored and hairy underneath.  European alder (Alnus glutinosa) is a non-native tree but one of the best for wet soils and can even survive standing water for a time.  A disadvantage of alders in our Pacific Northwest region is that they are prone to getting tent caterpillars in the summer.

Pacific Crabapple

The Pacific crabapple grows well in moist soil and has fragrant white spring flowers and edible fruits.

Native nurseries sometimes sell the Pacific crabapple (Malus fusca), which is a shrubby, small tree with fragrant white spring flowers and small yellow to purple-red fall apples that make delicious jams and jellies. In the wild, it survives along streamsides and moist woods, so it is perfect for lowland landscapes that are seasonally wet.


Plant weeping willows away from homes and give them plenty of space to grow.

Many willow (Salix spp.) trees will also tolerate wet soils and look attractive, though most are fast-growing and short-lived.  The Pacific Northwest native Hooker’s willow (Salix hookeriana) is a shrubby tree that can withstand high soil moisture and has attractive leathery leaves. White willow (Salix alba), which is native across much of North America, is not a tree for a small lot as it can reach 75-100-feet high and almost as wide.  The leaves are silvery beneath and often turn gold in the fall. Golden weeping willow (Salix alba ‘Tristis’), has young stems that are bright yellow and are often used in flower arrangements. Be aware that willows have shallow and invasive root systems and should not be planted near power or sewer lines. While a weeping willow is beautiful to look at, it needs lots of room.

Vine Maple

The fall leaves of vine maple are brilliant.

The Pacific-Northwest-native vine maple (Acer circinatum) has truly beautiful pale green leave with fall color of yellow, orange, and/or red. It is a small tree that rarely reaches heights above 20 feet. Several cultivated varieties have been bred, including the coral-red-stemmed Acer circinatum ‘Pacific Fire’, which has palm-shaped leaves that turn a rich yellow in fall.

If there is wet soil in your garden, others probably have similar issues. I like to advise gardeners to check around their neighborhood for yards with similar characteristics. Talk to other gardeners and look to see what trees they are growing. Most gardeners are usually very receptive about sharing plant information. Hearing what trees grow with success in your own neighborhood should give you some sound guidance.

Cool Weather Gardening in the Pacific Northwest

This gravel garden is creative and bright!

For those of you that have followed my monthly web articles, you are aware that I live and garden in a suburb of Portland, Oregon. While we are probably famous for our rainy weather, this year seems to be an exceptionally wet year. Not only wet, but some very cold days this past winter and the spring has continually been cool. We made a record (perhaps not something to brag about) these past few months by having the longest period without the temperature reaching 60 degrees since weather record keeping began in 1940 at the airport. When talking with various garden center personnel, the consensus seems to be that we are about two weeks behind what would be a “normal” spring season.

On April 6, at about 4:00 in the afternoon, we had one of the most torrential hail storms that I can remember. The sky just seemed to open; down came the hail, completely covering the ground, deck and roof. After the hail stopped, I looked out the window and it was as though we had just had a snow storm! And this is April! Earlier in the week, I was digging a hole to plant a shrub and after the shovel was into the ground about 12 inches, water started filling the hole from the bottom. I can never remember by soil being so saturated. Obviously this can be frustrating for gardeners but all the more reason to make plans for the day when sun does arrive. And it WILL arrive, we just do not know when.

BG-Seedling-1.5cuAll of these conditions make for a good reason to have a good supply of Black Gold Seedling Mix on hand. This is the ideal time to get seeds started so that once the weather warms; you will have plants to set outside. Whether you are starting vegetable or flower seeds, get them started now. Then when your seedlings are ready to transplant outdoors or you have bought transplants from a garden center, work into your outdoor flower and vegetable beds Black Gold Garden Compost Blend and along with it mix in a starter fertilizer. The starter fertilizer will supply a readily available source of nutrients as well as Mycorrhizae. Mycorrhizae has been added to the fertilizer as it has the attribute of helping plants draw in nutrients from the soil.

If your roses were pruned in February, there should be signs of buds swelling and breaking opening and perhaps new growth is emerging. Once new growth is 4-6 inches long, it is time to fertilize. A fertilizer formulated for flowers is ideal because it will have some fast- and slow-acting nitrogen as well as other nutrients all helpful in making roses look their best. Early in the season, like now, I also like to add Black Gold Alfalfa Meal. It provides needed nutrients naturally, including nitrogen, and breaks down quickly. While not all plants require a nitrogen boost, roses do. Since roses are primarily grown for their flowers and since rose flowers appear on new growth, adequate nitrogen will encourage new growth and hence more flowers.

Another great Pacific Northwest plant for gardeners is the rhododendron. For early blooming rhododendrons, once the flowering is over, it is time to fertilize. If your rhododendron needs pruning, just after blooming is an ideal time. If you wait too long, then you will cut off flower buds forming next year’s bloom. After bloom, it is also good to remove the old flowers and you will see there is a natural place to break them off at the base of the flower where it attaches with the stem. Fertilize with fertilizer for acid-loving plants. Make one application after bloom and then another in mid-summer. At the same time you are adding the fertilizer, consider amending your soil around the base of the plant. My favorite product for this is Black Gold Garden Compost Blend. I like to lightly work it into the soil (rhododendrons have shallow roots so do not cultivate deeply), add fertilizer and then water. It gives the soil a very polished and “finished” appearance.

While we hopefully will have some sunny days soon, do not rush the season by planting summer vegetable plants. Last year I heard so many gardeners lament their early rush to plant summer vegetables and then experiencing the failure with plants performing poorly or dying. Warm season vegetables like tomatoes, basil, cucumbers, beans, and squash are called warm season for a reason. These plants all need warm days and nights and planting too early will result in failure.

Summer will arrive, just don’t rush it!