Question from Bill in Minnesota:
Response from LessLawn:
I'm looking for shade and drought tolerant plants to be put below windows.
| The spring buds of sweet woodruff soon open into four-pointed stars.|
I've put together a list of plants you can investigate. I've added what I know about them, but you'll want to double-check each plant's requirements with its supplier. Since you are putting these in below windows, they'll be close to the building's foundation, which creates a lime-rich (as opposed to acidic) soil. If the plants are under the eaves, they may be in an especially dry zone.
Your eventual mix of plants will depend on your site's specific conditions, how much color and seasonal change you prefer, plus how much maintenance you're willing to do. I've separated the plants into categories that might help you combine a group of plants in a pleasing design. (See the sidebar at right for descriptions of the categories.)
Perennials for lasting foliage or flowers
Perennials for decorative accents
- Hardy Geranium or Cranesbill (Geranium cultivars and species): Size and habit vary by cultivar, but most will form a loose clump about a foot high that spreads wider every year until it's about a yard across. Flowers bloom nearly all summer in pink and purple tones. Flowers are about an inch across and single (a row of petals around a center). They're scattered at the beginning and end of the season, but they will create a mass of color at the height of bloom. Long-lived and disease-resistant, this plant can be used for patches of groundcover, decorative accents, or to wind among taller, spiky plants.
- Bergenia (Bergenia cordifolia): Large, glossy leaves are green with red veining and turn brown-red in autumn. Foliage forms a clump about a foot high and wide, and a cluster of bright pink flowers rises just an inch or two above the leaves in spring.
- Solomon's Seal (Polygonatum multiflorum): Native woodland plant forms an arching clump of stems two to three feet long. A clump can grow to four feet across over time and never needs dividing. White, evenly spaced bells dangle from the stems in spring, followed by blue-black berries. Likes acid soil. Can take deep shade.
- Wild Ginger (Asarum canadense): Downy green, heart-shaped leaves form clusters that thickly cover the ground. Inconspicuous brown flower develops under the leaves. Can tolerate deep shade. Six to eight inches high and will spread over time to form a colony.
- Bugbane (Cimicifuga racemosa): Decorative divided leaves form a clump two to three feet high and wide, from which rise white plumes of flowers in late summer. The flowers have a distinct but not unpleasant smell that keeps away insects. Has the look of a shrub by autumn, but dies down to the ground every year. Likes moist but well-drained soil; leaves will turn brown around the edges if too dry. Several purple-leaved cultivars (such as 'Black Beauty') offer striking foliage but are less vigorous.
- Jack-in-the-Pulpit (Arisaema triphyllum): Native woodland plant that likes rich, moist soil and can tolerate deep shade. Each stem emerges in spring with two leaves, each deeply divided into three parts. The unusual tubelike flower is green and may have purple stripes, and it is followed by a cluster of red berries in fall. The plant looks rather menacing but isn't poisonous, though it is bitter-tasting.
- Lady's Mantle (Alchemilla mollis): Ruffled leaves stay bright spring green with silvery fur through the growing season. In early summer, sprays of tiny lime green flowers rise from the neat mounds of foliage. Great for choking out weeds because it covers the ground under it completely. Each foliage mound is eight to ten inches high and grows to two feet across. Flowers are held a foot or so above foliage. Invariably, those who mention this plant remark on its ability to catch drops of rain or dew, which glow silver as they are held by the hair on the leaves.
- Corydalis (Corydalis lutea): Through most of the growing season, small clusters of yellow tubular flowers are held just an inch above a lacelike mound of foliage. Foliage mound grows to a foot high and wide. Needs some direct sun. May self-sow.
- Lungwort (Pulmonaria longifolia): Long, pointed dark green leaves with white spots brighten a shady place. Spring blooms can be pink, white, or blue and appear at different times depending on the cultivar. Leaf clumps can grow 10-12 inches high and up to two feet across. Individual leaves vary from six to ten inches long.
- Woodland Aster (Aster cordifolius): Like mums, only with smaller flowers, these asters grow in clusters of stalks to two feet high and produce lavendar flowers in late summer that last through fall. Tolerate heavy shade and dry soil. Their light-colored flowers glow in the evening and liven up a dark area. May self-sow.
- Coralbells or Alum Root (Heuchera cultivars): There are green-leaved and purple-leaved cultivars and some with white-and-green variegated foliage. H. micrantha var. diversifolia 'Palace Purple' is especially nice, forming a cluster of maple-shaped leaves that grows to a couple of feet across and stays about a foot high, with the larger leaves up to six inches across. In summer, a stalk with an airy spray of tiny shell pink flowers rises from the center of the clump. The flowers on other cultivars can be white to pink to bright red. Leaves are interesting year-round. Can scorch in full sun, but tolerates most other light conditions; survives well on the north side of a building if it's not too dark.
- Hostas (Hosta cultivars): Mainly loved for their sturdy foliage that emerges early and stays through the growing season, hostas also have flowers (some quite decorative and a few fragrant). See photos.
Shrubs for All-Season Structure
- Columbine (Aquilegia canadensis): Single stems rise from the ground in spring and flower, then die back. Self-sows but not invasively. Plants will hybridize freely with other nearby columbines. Each plant lasts only a year or two, but a colony can continue for years if allowed to self-sow. The native woodland species has red and yellow flowers with long spurs.
- Virginia Bluebells (Mertensia virginica): Forms a sturdy clump about sixteen inches high and up to eight inches across. Flowers bloom in the spring and are blue tubes edged with purple/pink. This native woodland understory plant thrives without much sunlight and can add accents of color early in the season. Might need a more moist environment than you can offer, and the dying foliage takes a while to sink back to the ground, which might bother a tidy gardener.
- Monkshood (Aconitum cultivars): Dark blue/purple or white blooms on tall spikes in late summer. Poisonous root, so you wouldn't want to plant this where children play. May blow over if not staked, so again, more work for the tidy gardener. However, it adds color at a time when you may be itching for a change. Foliage attractive year-round. May need supplemental moisture.
- Bleeding Heart (Dicentra spectabilis): Ephemeral plant forms a cluster of arching stems of lacy foliage. In spring, smaller arching stems display rows of pink heart-shaped flowers, each with a white pendant hanging from it. After blooming, the entire plant disappears until the next spring. Enjoys morning sun and afternoon shade.
- Spiderwort (Tradescantia x andersoniana): Clump of arching, straplike foliage eight to twelve inches high is dotted with purple three-petaled flowers, each with a prominent ring of yellow stamens. Leaves emerge from the ground early in the spring, and flowers last six to eight weeks in summer.
- Perennial Foxglove or Straw Foxglove (Digitalis lutea): Unlike other foxgloves, this perennial stays put and doesn't self-sow. Basal rosette of thin, pointed leaves hoists a long stalk that carries a row of cream-colored bell-shaped flowers up one side. Flowers are smaller and daintier than those of hybrid foxgloves, so the plant looks more like a wildflower.
Groundcovers to plant under perennials and shrubs
- Siberian Cypress (Microbiota decussata): Low shrub with finely divided foliage that is dark green through the summer and turns burgundy purple in winter. Branches are raised six to twelve inches above the ground and can eventually stretch ten feet across, though mine have only grown four to six inches a year. Good for adding interest above a low groundcover.
- Spreading Yew (Taxus x media 'Densiformis'): Yews tolerate even full shade and any moisture level except standing water. Their vibrant dark green needles liven up a winter scene. Left unpruned, this shrub will grow three or four feet tall and five to eight feet across, and will form a dense mound that should block out most weeds. Makes a nice background plant, in front of which you can display decorative flowers and lighter foliage. Also likes lime, so will thrive near the foundation of a building.
Note: You'll want to set a significant barrier between these creepers and any bordering lawn, as they could get into the lawn and out-compete the grass. Edge with a mowing strip at least six inches across for best protection and lowest maintenance.
Annuals for Supplemental Color in Shade
- Bugleweed (Ajuga reptans): Dark blue/purple flowers in spring stand up on short spikes from basal rosettes connected by underground stems. Forms a thick cluster of leaves that will completely cover open ground and even venture into the heavy shade under large-leaved foliage such as hosta.
- Sweet Woodruff (Galium odoratum): White star-shaped spring flowers top short spikes of fresh green leaves that shoot up from running stems just under the soil's surface. Forms a thick cluster of leaves that will completely cover open ground and even venture into the heavy shade under large-leaved foliage such as hosta.
- Creeping Thyme (Thymus serpyllum): Thick mass of curly stems and tiny-leaved foliage four to six inches high that spreads around and under everything. Smells great when crushed underfoot or brushed against. Can use for cooking. Bright pink flowers cover the foliage in spring.
- Mother-of-Thyme (Thymus praecox): Requires part-sun or at least bright indirect light. Very short (less than an inch) groundcover spreads across open ground but stops at areas that are too shady, such as under heavy foliage. Covered with bright pink flowers in spring. Smells great when crushed and can be used for cooking.
- Spotted Dead Nettle (Lamium maculatum): Various cultivars have different patterns of variegated green-and-white foliage and different colors of flowers from white to yellow to pink. Spreads through a shady area and lightens it up. Can take deep shade. Prostrate (less than three inches high) and spreads with above-ground stems, so can easily be curbed by clipping if necessary.
- Wild Blue Phlox (Phlox divaricata): Loose, creeping plant about a foot tall with light blue or white star-shaped flowers sprinkled across bright green foliage. Weaves through other plants. Blooms in early spring.
- Lily-of-the-Valley (Convallaria majalis): Six-inch-high plant with tulip-like leaves and delicate sprigs of white flowers in spring can form thick colonies over time in even deep shade.
- Coleus (Coleus hybrids): Size and color vary widely, but many have striking patterns of bright green, red, and white foliage.
- Flowering Tobacco (Nicotiana alata): Grows two to three feet high and a foot wide, depending on cultivar. Flowers come in pastel shades and release their scent at night; might be nice under windows or near an outdoor patio.
Though I didn't create a list of ferns, grasses, and sedges for shade (we'll have to save that for another day), many plants in these categories would create pleasing contrasts to the foliage of the plants I did list. Some to investigate: Lady Fern (can take dry shade), Bottlebrush Grass (has seed heads shaped like a bottlebrush), and Pennsylvania Sedge (clump-forming, grasslike perennial).
Hope this answer will help you plan and plant under your windows. Write and let us know what you decide to try and how it works!
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