Shade gardens generally look good with less maintenance than a sunny garden, because the weeds which usually grow prefer full sun rather than dark shaded areas. Shade gardens are also better protected from summer and winter damage because nearby trees and walls make an excellent screen against dry summer heat and cold drying winter winds. Shaded areas naturally create cool, refreshing, tranquil retreats from the hot summer sun and heat.
Full sun is considered to be six or more hours of direct, uninterrupted sun per day. Partial sun is three to six hours of sun, and less than three hours of sun is light shade. There is also dappled shade where light filters through overhanging branches. The amount of shade an area gets will also depend on the season. Many of the great wild shade flowers, such as bloodroot, Dutchman's-breeches, bleeding heart, jack-in-the-pulpit, and trillium, blossom before the leaves have fully grown out, and get adequate sunlight in the cool of the spring. When the leaves are fully expanded, you have a hard time even finding these plants.
Light is not the only concern when gardening in the shade. Frequently, inadequate moisture can be a problem. The thick canopy of a large tree or the overhang of a house will act as an umbrella, deflecting rainfall away from the ground directly beneath it. Trees and shrubs will also compete with smaller plants for every drop of moisture that reaches the ground. Plants which are growing in these conditions need to be watered regularly even during times of seeming adequate rainfall.
Trees and shrubs fill the soil with feeder roots which greedily use up nutrients as readily as they are applied. It often seems that the more you water and fertilize, the more roots with which you have to contend. Yet adequate fertility is an absolute for all plants, because without it they are bound to be small and their growth will be weak. A spring application of a balanced fertilizer is necessary, followed by one or two applications as the season progresses. This will help shade plants survive the competition of tree and shrub roots. The fall leaves often integrate perfectly into a shade garden. Leave them where they fall and they will supply a natural mulch that regenerates and enriches the soil while helping to suppress weeds. If the leaves are large and leathery, run a lawn-mower over them to chop them up and then spread them around your shade plants.
If you are using flowers, white, pale pinks and blues and lemon yellows reflect light better than deep reds and oranges. Foliage which has leaves which have white and yellow stripes, are variegated or marbled, or that are silvery-mottled, will stand out and brighten shaded areas. Leaves which have these colors are more durable than flowers because they last through the entire growing season.
Beautiful shade gardens can be developed by combinations of contrast of foliage color, texture and plant form. Light, airy fern fonds stand out from heavy, oblong hosta leaves. Both these leaves will stand out if at their base is a low growing ground covers. The subtle differences in the shades of foliage becomes more distinct when there are no flowers to steal the show. Nature provides a vast and pleasing array of foliage colors: blue-green, apple-green, dark-green, with many shades in between.
The following are lists of plants which do well in light and partial shade. Those with * are suitable for heavy shade.
ANNUALS: balsam, wax begonias, browallia, vinca, coleus, feverfew, fuchsias, impatiens, lobelia, mimulus, dwarf salvia, and wishbone flower.
BULBS: tuberous begonias, crocus, daffodils, grape hyacinths, scillas, snowdrops, and species tulips.
GROUNDCOVERS: ajugs (bugleweed), *barrenwort, *wild and European ginger, *goutweed (bishop's weed), *hosta lilies, *lily of the valley, *Japanese spurge, *periwinkle, and *wild violets
HERBS: basil, chervil, chives, coriander, mints, parsley, sage, sorrel, and tarragon. These will grow but they will not be as large or a full as if grown in the sun.
PERENNIALS: astilbe, bergenia, bleeding heart, columbine, coral bells, *daylilies, *ferns, forget-me-nots *hosta lilies, leopardsbane, meadowsweet, monarda, monkshood, trollius (globe flower).
WOODLAND FLOWERS: *bellwort, bloodroot, cardinal flower, *Dutchman's breeches, *foam flower, fringed bleeding heart, harebells, hepatica, *jack-in-the-pulpit, Jacob's ladder, *lungwort, *meadow rue, rue anemone, white or black snakeroot, *Solomon's seal, spring beauty, *trillium, *Virginia bluebells, wild columbine *wild violets.
Kyle Schulz is a Wadena County Master Gardener from Sebeka, and the regular gardening columnist for the Wadena Pioneer Journal.