Turf-type grass is the best of all groundcovers because it can be walked upon. No other plant quite fits that use. The groundcovers that we list in this chapter are those plants that can be expected to grow close enough together to form a dense cover over the soil. They are too high for play or traffic areas, but not so high that they become a barrier. For example, a mass planting of Pfitzer juniper would become large enough to deter charging buffalo, therefore we would not list them with our groundcovers. On the other hand a mass planting of Cotoneaster dammeri ‘Lowfast’ would grow together and make a cover only about a foot deep, thus qualifying nicely as a groundcover. Some in the following lists are woody-type plants, others are herbaceous perennials. Members of both groups can be found in their respective chapters elsewhere in this book to help you learn more about the use characteristics of a plant that catches your interest.
The groundcover lists are not to be considered complete. In fact we encourage you to visit retail nurseries and garden centers, arboretums and experiment stations, where a constant stream of new plant types can be found. Look at established landscapes, parks, and municipal plantings for examples of groundcover plantings. As you find others, add them to our lists. That is what will make this book most useful to you.
Before trying to establish a groundcover, do some careful planning. Generally the nurseryman who sells the plants can tell you how far apart to plant them so you know how many are needed for the square footage of your site. Look at the site you are planting with a critical eye. How about perennial weeds, like perennial thistles or quackgrass, or horror of horrors, horsetail rush (Equisetum arvense). These need to be dealt with before planting your first groundcover plant. They are very difficult to control after the groundcover plants are in. Tilling and raking out roots will help a little, or use glyphosate (Roundup) before starting to prepare the soil, while the weeds are tall and leafy. After several weeks, till and rake out as many roots as possible. Mulching will help to keep annual weeds from taking over before the groundcover gets established.
Planting in the higher elevations is best done in spring when the ground warms. In the lower areas you can plant in spring or early fall. After planting, keep the new plants well watered, fertilize them several times through the year while they are actively growing, and you will be surprised at how fast they fill the gaps and become a true groundcover.
In some landscape situations you will need plants that can tolerate the extremes of full sun or full shade. An example would be if you are planting an area that extends across the yard from shade trees to open space and back again to the microclimate of shade trees. Both conditions may exist in any garden, and in varying amounts. Luckily, we have a lot of plants for our use that are very adaptable. As you travel through the Pacific Northwest, watch for the succession and occurrence of groundcovering plants and how they relate to the light. This list is only a starter that you can add to as you run across others.
Carpet bugle (Ajuga reptans) |
All PNW |
Kinnikinnick (Arctostaphylos uva-ursi) |
All PNW |
White bishop’s hat (Epimedium youngianum ‘Niveum’) |
All PNW |
Pink bishop’s hat (Epimedium youngianum ‘Roseum’) |
All PNW |
Winter creeper (Euonymus fortunei) |
All PNW |
Wild strawberry (Fragaria chiloensis) |
C, LV, LM, DV |
English ivy (Hedera helix) |
All PNW |
Salal (Gaultheria shallon) |
C, LV, LM, DV |
Ground ivy (Glechoma hederaceae) |
All PNW |
Soapwort (Saponaria ocymoides) |
All PNW |
Creeping blueberry (Vaccinium crassifolium) |
C, LV, LM, DV |
Usually, we like to cover the ground quickly, so we use groundcovers that grow quickly. Some must be noted as ones that could easily get out of control. Those listed below should be planted in areas where they can do their own thing, where you will dedicate yourself to pulling them out within a given length of time, or in areas where you can restrict their roots in some manner. Remember, too, that the climbers can go up tree trunks or cover structures where you might not want them.
Bishop’s weed (Aegopodium podagraria) |
All PNW |
Meadow anemone (Anemone canadensis) |
All PNW |
Crown vetch (Coronilla varia) |
All PNW |
English ivy (Hedera helix) |
All PNW |
Chameleon plant (Houttuynia cordata ‘Chameleon’) |
All PNW |
Hall’s honeysuckle (Lonicera japonica ‘Halliana’) |
C, LV, LM, DV |
Mint (Mentha spp.) |
Varies |
Silver lace vine (Polygonum aubertii) |
All PNW |
Periwinkle (Vinca major ‘Variegata’) |
C, LV, LM, DV |
It is wise to check with other gardeners to see what their success has been with groundcovers that are suggested here. Invasiveness of plants can vary with climate and soil, but some plants are notorious everywhere. Hall’s honeysuckle is an above-ground invader of any structure or plant that will give it vertical support.
If you are planting a site that lies in full sun, you have probably decided that grass is a chore to care for. You will find that in the western region of the Pacific Northwest, one of the problems encountered when trying to grow a lawn is that the trees get in the way. They provide shade which encourages moss and discourages grass. However, if a groundcover sounds better to you because it takes less care (a groundcover generally does need less maintenance once it is established), or because you want something that gives the landscape more contrast and/or interest (you have selections that will give flowers, berries or foliage of different textures and colors available in the lists below), this section is written for you.
Juniperus horizontalis
While there are few rules to landscaping, low plants of a relatively fine texture should be the main groundcover in close-up situations. Taller groundcovers give a good effect at a distance and in heavier shade. Contrasting textures draw the attention, much as a variegated foliage groundcover will.
Where trees form dense canopies or tall shrubs cause the ground surface to be completely shaded during the day, you must search for something that will tolerate such conditions. Keep in mind, however, that for these hardy plants to survive you must supply water and fertilizer as needed to keep them from being starved out by the larger shading plants.
In the deep, cool and moist shade of the western part of the Pacific Northwest, the normal groundcover is moss, lots of it. If moss is already growing in your space, enjoy!
Bishop’s weed (Aegopodium podograria) |
All PNW |
Lady’s mantle (Alchemilla mollis) |
C, LV, LM, DV |
Wild ginger (Asarum caudatum) |
C, LV, LM, DV |
European ginger (Asarum europaeum) |
All PNW |
Bunchberry (Cornus canadensis) |
All PNW |
Kenilworth ivy (Cymbalaria muralis) |
C, LV, LM, DV |
Sweet woodruff (Galium odoratum) |
All PNW |
Wintergreen (Gaultheria procumbens) |
C, LV, LM, DV |
Box huckleberry (Gaylussacia brachysera) |
C, LV, LM, DV |
Ground ivy (Glechoma hederacea) |
All PNW |
Chameleon plant (Houttuynia cordata ‘Chameleon’) |
All PNW |
Dead nettle (Lamium maculatum varieties) |
All PNW |
Princess pine (Lycopodium clavatum) |
All PNW |
Oregon oxalis (Oxalis oregana) |
C, LV, LM, DV |
Japanese spurge (Pachysandra terminalis) |
All PNW |
Blue star creeper (Pratia pedunculata) |
C, LV, LM, DV |
Lungwort (Pulmonaria spps.) |
All PNW |
Creeping buttercup (Ranunculus repens ‘Pleniflorus’) |
All PNW |
Baby’s tears (Soleirolia soleirolii) |
C, LV, LM, DV |
Piggy-back plant (Tolmiea menziesii) |
C, LV, LM |
Periwinkle (Vinca minor) |
All PNW |
When selecting a groundcover, consider three factors—the height of the plant, the soil type you are planting into, and the exposure to sun or shade. Depending on your selection, height can range from a few inches to several feet. Some groundcovers can tolerate poor drainage, some can take alkaline soils, some demand a particular soil type. Choose shade-tolerant groundcovers for planting beneath shrubs and those that require full, open sunlight for planting exposed banks.
A slope presents both a problem and a challenge. Often we avoid the challenge by simply letting Mother Nature grow whatever grows naturally on slopes, given its soil type and climate. The problem is one of trying to blend the slope into the planted landscape, make it sort of fit the picture in your mind, and also prevent erosion. Erosion can happen either gradually, as soil particles wash away, or suddenly, when the entire hillside slides down. In the western part of the Pacific Northwest in January and February, 1996, many gardens were lost because of saturated soils that wanted to slide to the rivers. Not all plants will prevent erosion. In fact even trees that have grown for twenty years on the hillside may slide away during periods of excessive rainfall on silty-clay soils. However, the following groundcover plants are suggested for stabilizing average slopes. There are many other members of the species listed, but we list those that we deem the best for this purpose because of their deep-rooting capability. Add to the list as you run across others.
European beachgrass (Ammophila arenaria) |
C |
Marlberry (Ardisia japonica) |
C, LV, LM |
Feather reed grass (Calamagrostis acutiflora ‘Karl Foerster’) |
All PNW |
Crown vetch (Coronilla varia) |
All PNW |
Cranberry cotoneaster (Cotoneaster apiculatus) |
All PNW |
Bearberry cotoneaster (C. dammeri) |
All PNW |
Spreading cotoneaster (C. divaricatus) |
All PNW |
Ceanothus (Ceanothus gloriosus varieties) |
All PNW |
Bunchberry (Cornus canadensis) |
All PNW |
Winter creeper (Euonymus fortunei) |
All PNW |
Creeping wintergreen (Gaultheria procumbens) |
All PNW |
Salal (Gaultheria shallon) |
C, LV, LM, DV |
English ivy (Hedera helix) |
All PNW |
St. Johnswort (Hypericum calycinum) |
C, LV, LM, DV |
Sunburst St. Johnswort (Hypericum calycinum ‘Sunburst’) |
All PNW |
Sargent juniper (Juniperus chinensis sargentii) |
All PNW |
Andorra juniper (J. horizontalis ‘Plumosa’) |
All PNW |
Savin juniper (J. sabina) |
All PNW |
Hall’s honeysuckle (Lonicera japonica ‘Halliana’) |
C, LV, LM, DV |
Creeping Oregon grape (Mahonia repens) |
All PNW |
Japanese spurge (Pachysandra terminalis) |
All PNW |
Fountain grass (Pennisetum alopecuroides) |
All PNW |
Lowboy pyracantha (Pyracantha coccinea ‘Lowboy’) |
All PNW |
Gro-Low fragrant sumac (Rhus aromatica ‘Gro-Low’) |
All PNW |
Lingonberry (Vaccinium vitis-idaea) |
C, LV, LM |
On steep slopes, often the planting soil is thin or of a high clay content, making it difficult to establish plants quickly. Cutting pockets where composted manure or prepared potting soil can be worked into the existing ground will help the new plants to root quickly. Deep watering will be essential during droughty summer weather. A complete fertilizer, either Chemical or organic, will help.
Some groundcovers will grow and thrive in shade, others will live only in full open sunlight. The shade-tolerant plants vary in their degree of ability to sustain growth in the absence of full sunlight. That is why we have divided the shade plants into two groups; those that will take just enough to prevent a shadow, and those that will survive under a deck or among the trees and undergrowth of forest environs. Those that are vines in this list, even though they will live in shade, will tend to grow upward to whatever light exists and on whatever is handy (for example, English ivy will head for the sun, up the trunks of trees or the supports of decks).
English Ivy
Prostrate abelia (Abelia grandiflora ‘Prostrata’) |
C, LV, LM |
Sheep bur (Acaena spp.) |
C, LV, LM, DV |
Wooly yarrow (Achillea tomentosa) |
All PNW |
Bishop’s weed (Aegopodium podagraria) |
All PNW |
Carpet bugle (Ajuga reptans varieties) |
All PNW |
Dwarf bog rosemary (Andromeda polifolia ‘Nana’) |
All PNW |
Kinnikinnick (Arctostaphylos uva-ursi) |
All PNW |
Astilbe (Astilbe chinensis ‘Pumila’) |
C, LV, LM, DV |
Sedge (Carex conica ‘Marginata’) |
C, LV, LM, DV |
Snow-in-summer (Cerastium tomentosum) |
All PNW |
Dwarf plumbago (Ceratostigma plumbaginoides) |
C, LV, LM, DV |
Chamomile (Chamaemelum nobile) |
All PNW |
Corydalis (Corydalis spp.) |
C, LV, LM |
New Zealand brass buttons (Cotula squalida) |
C, LV, LM, DV |
Indian mock strawberry (Duchesnea indica) |
All PNW |
Bishop’s hat (Epimedium grandiflorum) |
All PNW |
Pink Queen bishop’s hat (Epimedium rubrum ‘Pink Queen’) |
All PNW |
Pink bishop’s hat (Epimedium Youngianum ‘Roseum’) |
All PNW |
Winter creeper (Euonymus fortuneii varieties) |
All PNW |
Ground ivy (Glechoma hederaceae) |
All PNW |
English ivy (Hedera helix) |
All PNW |
Plantain lily (Hosta selected spp. and vars.) |
All PNW |
Chameleon houttuynia (Houttuynia cordata ‘Chameleon’) |
All PNW |
Creeping lily turf (Liriope spicata) |
All PNW |
Grace Ward lithodora (Lithodora diffusa ‘Grace Ward’) |
C, LV, LM |
Creeping mahonia (Mahonia repens) |
All PNW |
Forget-me-not (Myosotis scorpioides) |
All PNW |
Japanese pachysandra (Pachysandra terminalis) |
All PNW |
Oregon boxwood (Paxistima myrsinites) |
All PNW |
Spring cinquefoil (Potentilla tabernaemontanii) |
All PNW |
Blue star creeper (Pratia pedunculata) |
C, LV, LM, DV |
Crinkle-leaf creeper (Rubus pentalobus) |
C, LV, LM, DV |
Purple clover (Trifolium repens ‘Atropurpureum’) |
All PNW |
Creeping blueberry (Vaccinium crassifolium) |
C, LV, LM, DV |
Inside-out flower (Vancouveria planipetala) |
C, LV |
Common periwinkle (Vinca minor) |
All PNW |
Barren strawberry (Waldstenia fragarioides) |
C, LV, LM, DV |
Plants that spill over the edge of a wall, trail down a slope, or cascade over rocks soften the overall landscape and help to give it a completed look. There are many situations in the average landscape where a trailing groundcover can add beauty and interest or lead the eye to another feature. Some can be used to scramble on the ground among taller plants. Vinca, for example, will grow and flow like a green stream with blue flowers. Some, like Polygonum, might get out of hand unless you give it reasonably constant attention and guide or restrict its normally robust growth pattern.
Rock jasmine (Androsace spp.) |
All PNW |
Bearberry cotoneaster (Cotoneaster dammeri vars.) |
All PNW |
Dorset heath (Erica ciliaris) |
C, LV, LM, DV |
Common winter creeper (Euonymus fortunei radicans) |
C, LV, LM, DV |
Pink Panda strawberry (Fragaria ‘Pink Panda’) |
C, LV, LM, DV |
Creeping baby’s breath (Gypsophila repens) |
All PNW |
English ivy (Hedera helix) |
All PNW |
Beacon Silver dead nettle (Lamium maculatum ‘Beacon Silver’) |
All PNW |
Creeping Jennie (Lysimachia nummularia) |
All PNW |
Ground ivy (Nepeta hederacea) |
All PNW |
Trailing phlox (Phlox nivalis) |
C, LV, LM, DV |
Creeping phlox (Phlox stolonifera) |
All PNW |
Silver lace vine (Polygonum aubertii) |
All PNW |
Soapwort (Saponaria ocymoides) |
All PNW |
Periwinkle (Vinca major ‘Variegata’) |
C, LV, LM, DV |
Dwarf periwinkle (Vinca minor) |
All PNW |
This category of plants is for those areas that are planted under the canopy of shade trees, or among the native trees that exist in your landscape. Trees remove a lot of water during the growing season. And, for those of you who have gardened in the Pacific Northwest for a year or more, you know that the summer growing season is also the dry season of this region. So, if you plant anything beneath your established trees, or within their system of roots, plan to water periodically during the summer. It also helps if you select plants that can tolerate shade and dryness. The following list will get you started. Keep in mind that even though these groundcover plants will tolerate dryness, they need supplemental water during their first growing season to become established.
Bellflower (Campanula takesimana) |
All PNW |
Lily-of-the-valley (Convallaria majalis) |
All PNW |
Bunchberry (Cornus canadensis) |
All PNW |
Bishop’s hat (Epimedium grandiflorum) |
All PNW |
Salal (Gaultheria shallon) |
C, LV, LM, DV |
English ivy (Hedera helix) |
All PNW |
Japanese spurge (Pachysandra terminalis) |
All PNW |
Soapwort (Saponaria ocymoides) |
All PNW |
Dwarf periwinkle (Vinca minor) |
LV, LM, DV, HD |
If your landscaping plans include trying to make the garden one of low maintenance, replace some of the more water demanding plants with some of these groundcovers that can tolerate dryness. Water these well through the first growing season so they can become established in your soil. Once they are established they will endure long periods of dryness, yet still retain their beauty and interest.
Blue star bellflower (Campanula poscharskyana) |
All PNW |
Dwarf plumbago (Ceratostigma plumbaginoides) |
C, LV, LM, DV |
Bearberry cotoneaster (Cotoneaster dammeri vars.) |
All PNW |
Sheep fescue (Festuca glauca) |
All PNW |
Creeping juniper (Juniperus spp. and vars.) |
All PNW |
Emerald carpet (Rubus pentalobus ‘Emerald Carpet’) |
C, LV |
Stonecrop (Sedum spp.) |
Varies |
Germander (Teucrium chamaedrys) |
All PNW |
Low, poorly-drained areas in the landscape can be most frustrating. This sort of challenge is one in which you must match resistance or tolerance to root-infecting diseases with the ability to grow and succeed in a wet soil environment. Poor drainage here does not mean that the soil remains swampy throughout the entire year, but does indicate that during the rainy season in the western part of this region you would expect the roots of your plants to be wet. Here are a few that we have observed throughout the years and found to be surprisingly successful in this sort of situation. We suggest them to you for trial. Add to the list—if wet soils are the nemesis of your garden—so it will become more valuable as your garden matures. One additional consideration is to develop a drainage system for your yard, or for those particular spots that remain wet for long periods.
Bog rosemary (Andromeda polifolia) |
All PNW |
Japanese ardisia (Ardisia japonica) |
C, LV, LM |
Corsican sandwort (Arenaria balearica) |
C, LV, LM, DV |
Wild ginger (Asarum spp.) |
C, LV, LM, DV |
Sedge (Carex conica ‘Marginata’) |
C, LV, LM, DV |
Bleeding heart (Dicentra formosa) |
All PNW |
Cross-leafed heath (Erica tetralix) |
C, LV, LM, DV |
Algerian ivy (Hedera canariensis) |
C, LV, LM |
Chameleon plant (Houttuynia cordata ‘Chameleon’) |
All PNW |
Bird’s-foot trefoil (Lotus corniculatus) |
All PNW |
Pennyroyal (Mentha pulegium) |
All PNW |
Spring cinquefoil (Potentilla tabernaemontanii) |
All PNW |
Blue star creeper (Pratia pedunculata) |
C, LV, LM, DV |
Dwarf periwinkle (Vinca minor) |
LV, LM, DV, HD |
This is a list of those nifty little plants that can be tucked into a spot between stepping stones or beneath a rock or in spaces between flagstones. Look also at the list of herbaceous perennial plants for rockeries for additional plants that suit this category.
Woolly yarrow (Achillea tomentosa) |
All PNW |
Rupture-wort (Herniaria glabra) |
All PNW |
Pennyroyal (Mentha pulegium) |
C, LV, LM, DV |
Requiem mint (Mentha requienii) |
C, LV, LM |
Raoulia (Raoulia australis) |
C, LV, LM, DV |
Rock breaker (Saxifraga spp.) |
All PNW |
Stonecrop (Sedum spp.) |
Varies |
Creeping thyme (Thymus praecox arcticus) |
All PNW |
Foamflower (Tiarella cordifolia) |
All PNW |
Soapwort (Saponaria pumilio) |
All PNW |
Speedwell (Veronica oltensis) |
All PNW |
Plants selected for the seacoast part of this region must survive elements like winter gales along with the normal salt-laden winds. Additionally, there are differences in growing conditions, such as cool summer temperatures accompanied by fog. And there is a wide range of soil types, ranging from sand to clay, often within the same landscape site. Here are some suggestions for plants that will survive such conditions. Keep your eyes open for other plants that fit your needs as you travel within the coastal areas.
Arctostaphylos uva-ursi
European beachgrass (Ammophila arenaria) |
C |
Kinnikinnick (Arctostaphylos uva-ursi) |
All PNW |
Point Reyes ceanothus (Ceanothus gloriosus) |
All PNW |
Ceanothus (Ceanothus griseus horizontalis vars.) |
C, LV, LM, DV |
Beach strawberry (Fragaria chiloensis) |
C, LV, LM, DV |
Lydia broom (Genista lydia) |
C, LV, LM, DV |
Genista broom (Genista pilosa) |
C, LV, LM, DV |
English ivy (Hedera helix) |
All PNW |
Horseshoe vetch (Hippocrepis comosa) |
C |
Creeping St. Johnswort (Hypericum calycinum) |
C, LV, LM, DV |
Creeping juniper (Juniperus horizontalis vars.) |
All PNW |
Lithodora (Lithodora diffusa) |
C, LV, LM |
Japanese honeysuckle (Lonicera japonica) |
C, LV, LM, DV |
Silver lace vine (Polygonum aubertii) |
All PNW |
“The major factors that a landscaper should consider when planning a coastal landscape include the distance that a garden site is from the ocean, the amount of exposure the site is subject to as a result of prevailing northwest winds, the amount of sunlight the site receives, and the quality of soils found at that site.”—Bill Rogers, Oregon State University extension agent, Newport, Oregon