(From “Singing the Praises of Gardening in the Shade” in June 2006 “Desert Plants.” Read the full article on Maggie’s
Terra Flora website under Writings.)
Not all shade is created equal. Full shade conditions exist in areas under trees and conifers with tight branch patterns and dense foliage. The canopy of these trees acts like a giant umbrella diverting water; so often the soil under these trees is dry. Full shade can also be on the north side of structures never reached by direct sun from October to early April.
Partial shade is created when trees, shrubs and evergreens with more open branches and foliage permit sunlight to move through them, creating the play of shadow and texture in a partially shady habitat. A site facing east, with morning sun and afternoon shade, creates a similar condition. And, there is always variation within - areas close to the house which go into shadow earlier or under deciduous trees open to winter sun but under full canopy during summer. Many of our bulbs that receive a wee bit of glory then bow out early and go to sleep and most plants that manage in full shade and are well mulched, will accommodate to this type of environment.
Partial shade is ideal for a wide range of materials. Some partial shade lovers tucked in behind large stones or larger plants, perform just fine facing south. It’s all about microenvironments. For example, some plants such as clematis like to have their roots in shade and their tops in more sun. 
Walking along shaded forest paths, we see plants competing successfully for nutrients in a crowded setting. Factors contributing to this adaptability include geology and rock type, air movement, deep and cool root run and plant association.
Our shade garden soils benefit from mirroring these conditions by opening and aerating the soil and incorporating high quality compost and appropriate amendments. We use Bio-Dynamic compost - which helps to retain moisture, sustain the soil’s vitality and balance the soil alkalinity – plus 2-3 inches of leaf mold (half decomposed appropriate leaves). A thick mulch buffers temperature extremes and helps to retain moisture and soil coolness.
Grouping materials with rhythmic distribution of contrasting shapes and colors sustains the design and develops its character. The size of these groupings should relate to the size of the garden. Utilizing scale in layering the planting directs the eye from tree canopy to ground level harmoniously. Featuring diffuse -transparent plants with more defined ones is useful too.
Choosing plants with good foliage carries the shade garden beyond bloom. Shape is especially relevant to foliage and useful in the front and middle grounds for rhythmic repetition, including bold leaves for punctuation. Artful scattering of key plants or plant shapes like loose groups of spires or plumes, keeps the design unified and increases a sense of spaciousness throughout the garden. Variegation in leaves or as a background to white/pastel clumps can add coherence and rhythm.
Color can help link the garden to the architecture, reflecting the theme and creating atmosphere, eliciting excitement and delight. Whites shimmer, blues are luminous and chartreuse greens are like pools of sunlight. Varying densities and distribution of color anchor and give structure to the garden. Related, complementary and mirrored shapes related by color bring a naturalness to the composition. Form and color led the eye around the garden.
Grasses offer both evergreen and structural continuity by adding framework and counterpoint to horizontals and other verticals, yet remaining transparent. They animate movement and lend a comfy harmonizing naturalness. Selections to consider for a range of shade are Japanese Forest Grass, Carex, Wild Oats and Variegated Miscanthus, while short tussocks as Deschampsia Northern Lights and flexuosa, Ophiopogon planiscapus nigrescens, Luzula sylvatica, Melica and Sesleria are fine accents. Weavers like Panicums, Molinas and Thalictrums, add depth and surprise.
By taking our cue from nearby forests, developing familiarity and experience with cultural needs of plants, and playing with convivial neighbors and striking accents, we evolve a nature-inspired aesthetic equipped with resources for designing and growing sylvan gardens to our hearts’ delight.
Maggie Lee is the proprietor of Terra Flora - a garden design-build landscape firm. She can be reached at 505 982-6879 or through the Terra Flora website.