Organic Gardening: Learn how to choose and nurture shade plants
There are gardeners who consider a walk in the woods to be the best education. And Michigan’s woods are full of curious, beautiful and often understated plants that have co-evolved with insects and other wildlife. Although, one might wonder what actually constitutes a “native” in our changing climate, the native plants – and the wildlife that depend on them – seem worth preserving if only because some of us find them especially beautiful.
Midwest shade plants in particular, offer a broad pallet of greenery as well as unique textures, flowers and berries. But nurturing these species requires a mindset attuned to the ecological context where these plants evolved.
Bill Snyder – the owner of Wildtype Native Plant Nursery in Mason – says that gardeners are “always thinking that shade is shade”, whereas successfully growing natives means differentiating between deep-shade, partial shade and sun. The gardener may also need to account for relative levels of moisture because many shade perennials evolved to grow in moist or even swampy conditions.
Large trees in the forest overstory usually determine the amount of shade. “(There’s) a whole continuum of shade,” Snyder says, with oaks that let in lots of dappled sunlight to maples that let in very little. Pines and spruces block almost all light and severely limit planting underneath. Residential gardeners also need to observe how much shade is created by buildings and other structures.
Areas of partial shade offer the most options by far. Wild ginger is an especially good plant for these areas. Its flowers are inconspicuous under the spreading foliage, but the heart shaped leaves and rich green color give it a broad appeal. “This is not a granola plant,” Snyder says, “this plant has a personality.” It’s also widely adapted to varying levels of shade, filling a similar niche as hostas. However–as with many natives–don’t expect wild ginger to take over immediately. Snyder says it often takes this species two or three years to establish itself and spread.
Great plants for woodland borders and light shade include Solomon’s seal and the visually similar Solomon’s plume and starry Solomon’s plume. Like many natives, these are grown as much for their upright form and attractive leaf texture as flowers. Starry Solomon seal and Solomon’s plume both have attractive white flowers, with those of the latter turning into red berries in late summer.
Blood root and doll’s eyes are other great plants for dappled shade that could take the place of nursery standards like astilbe or coral bells. Doll’s eyes is especially striking, its flowers turning into white berries with a black center that give the wildflower its name.
In the dense shade created by Norway maples that leaf out early and hold onto their foliage until late in the year, gardeners could replace vinca or pachysandra with a northern bush honeysuckle (not to be confused with the invasive non-native honeysuckles). Large-leaved aster, heart-leaved aster, zig-zag goldenrod and bluestem goldenrod also do well in fairly deep shade and provide color–especially in summer and fall – although they all require a decent amount of moisture.
Zig-zag goldenrod can be somewhat aggressive. Snyder however, refers to it as “opportunistic”, suggesting its spreading habit performs a valuable function on disturbed ground. At any rate, it’s not nearly as aggressive as vinca, for example, and can be a good plant to fill out a space, attracting pollinators in late summer with its bright yellow flowers.
Ferns are another option in the shade and provide a counterpoint in texture and color to the Solomon’s seals. However, they’re not always easy to grow. Snyder said he’s had success with sensitive fern–which has a spectacular golden-green color–in wet areas with some shade. Maidenhair ferns are also attractive. They have delicate foliage with tiny, gingko-like leaflets, but they need wet soil and protection from the wind.
Many of the plants discussed here can be found at nurseries belonging to the Michigan Native Plant Producers Association, which are listed at www.mnppa.org. There are also a few catalogs such as Prairie Nursery out of Wisconsin that ship native or near-native plants to Michigan.
Finally, Snyder says that when its actually time to plant, don’t make too much of a fuss. Many Michigan natives thrive in suboptimal conditions. Unless the ground is very compacted, don’t feel like you need to cultivate the soil. If it’s heavily compacted, simply work it a bit with a digging fork. Aside from clearing the site of weeds, any sort of fertilizers or soil amendments are unnecessary. After planting, dress the soil with a layer of wood mulch.
You may need to water for the first year or so, but from then on these species should thrive with minimal care. A fully planted landscape doesn’t need additional mulch, provided you allow the leaf litter to decompose in place. What the gardener is cultivating here is essentially a forest. Although some weeding is inevitable, the work is mostly in the planning with nature doing the rest.
Contact Brian Allnutt at email@example.com.