Foundation Plantings
The conventional foundation-planting look is easily achieved using locally native plants, if that is to your taste, or you could liven it up a little by choosing a more relaxed look.
Check the soil
Concrete from foundations, sidewalks and driveways leaches into the soil, making it more alkaline (raising the pH). Some plants require a lower pH to thrive. Examples include blueberries, raspberries, rhododendrons, hollies and azaleas. So check the pH. You could amend the soil to lower the pH, but you will have to keep it up indefinitely, and it is a lot easier to choose alkaline-tolerant plants (see the list below).
Shrubs
Shrubs are the backbone of the garden, softening the lines of the building and providing food and shelter for birds. See our page on native shrubs for many popular examples.
Not just shrubs
Shrubs are not the only option for foundation plants. Vines such as Coral Honeysuckle can be trained up on trellises. Taller clumps of grasses such as Switchgrass will persist all winter and make for interesting shrub substitutes in full sun. Evergreen ferns do well in the shade and are also helpful for the place in front of any shrubs that have gotten leggy. Short trees can add height and interest. Most should be placed at least ten feet from the foundation.
Adding a ground layer finishes the look and adds habitat value. Click here to learn about native ground covers.
Tucking spring ephemerals - the native equivalent of crocuses and daffodils - under deciduous shrubs will give you something to look for as winter loses its grip.
Do you enjoy pruning?
Some native shrubs can be shaped by shearing. Click here for a list. You will save yourself a lot of work, though, if you choose plants that will be the right size when mature without pruning. The plants will be happier, too, and will display their full beauty. Shorter shrubs such as New Jersey Tea and Shrubby St. John’s Wort fit nicely under windows. Other native species have been propagated as shorter cultivars. Taller plants are often placed next to corners. Big plants such as Elderberry, Hazelnut, and Silky and Gray Dogwood are beautiful in front of windowless walls.
How important are evergreens?
We often expect foundation shrubs to be evergreen - and there are a few native evergreens available as well as evergreen ferns - but deciduous shrubs are just as nice. Some are quite interesting in winter, such as Winterberry and Red Chokeberry with their bright red berries, and Smooth Hydrangea with its persistent flower heads. It is also much easier to watch birds that are perching on bare branches.
Click here for a list of evergreen plants.
Plant that tolerate alkaline soil (pH> 7.0)
Shrubs
Smooth Alder (Alnus serrulata) pH 5.5-7.5
False Indigo (Amorpha fruticosa) pH 6.8-7.2
Devil’s Walking Stick (Aralia spinosa) pH 5.5-7.5
Groundsel Tree (Baccharis halimifolia) pH 7-8.5
American Beautyberry (Callicarpa americana) pH 4.8-7
New Jersey Tea (Ceanothus americanus) pH 6.8-7.2
Buttonbush (Cephalanthus occidentalis) pH 6.1-8.5
Sweetfern (Comptonia peregrina) pH 4-7
Silky Dogwood (Cornus amomum) pH 6.1-7.5
Gray Dogwood (Cornus racemosa) pH 6.1-8.5
American Hazelnut (Corylus americana) pH 6.1-7.5
Smooth Hydrangea (Hydrangea arborescens) pH 6.1-8.5
Dense St. James Wort (Hypericum densiflorum) pH 5.5-7
Shrubby St. John’s Wort (Hypericum prolificum) pH 6.8-7.2
Virginia Sweetspire (Itea virginica) pH 5.1-7.5
Evergreen Bayberry (Morella caroliniensis) pH 4.5-7
Ninebark (Physocarpus opulifolius) pH 6.1-8.5
Roseshell Azalea (Rhododendron priniphyllum)
Trees
Serviceberry (Amelanchier species) pH 5.5-7.5
Paw Paw (Asimina triloba) pH 5.2-7.2
Allegheny Chinquapin (Castanea pumila) pH 4.5-7.5
Redbud (Cercis canadensis) pH 4.5-7.5
Flowering Dogwood (Cornus florida) pH 5-7
Cockspur Hawthorn (Crataegus crus-galli) pH 4.5-7.2
Vines
Crossvine (Bignonia capreolata) pH 6.1-8.5
Virgin’s Bower (Clematis virginiana) pH 6.1-8.5
False Jasmine (Gelsemium sempervirens) pH 5.5-8.5
Coral Honeysuckle (Lonicera sempervirens) pH 6.1-7.5
American Wisteria (Wisteria frutescens) pH 4-7
First Church of Christ, Scientist, Arlington
IWinterbery (Ilex verticillata) at Maryland House, I95
Christmas Fern (Polysichum aristichoides) - Evergreen
Vienna Vintner
Overused Foundation Plants and Native Alternatives
Planting location
Don't plant too close to the wall. The plant needs room, and you need room behind it to access the wall.
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2-3 foot high shrubs - 3 feet from the wall
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3 foot high shrubs - 4-5 feet from the wall
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Trees - 10 feet or more from the wall
"Ask the Experts" videoconference with landscape designerAdele Kuo, Decofootprints