Our townhouse has a southern exposure, with deciduous trees and the garden on the south, east and west sides, and a common wall with another home to the north. From November through early April, with the leaves off the trees we get a lot of sun, helping to keep the house warm and the heating bills low. As the leaves unfold, the house and garden is well shaded, minimizing the need for air conditioning. “Passive solar”, courtesy of nature, free for the taking. We love the trees.
In nature, different species need to spend parts of their lives at different levels of the forest, some at or below ground level, some just above it, some a few feet higher in shrubs, and others in the trees, even all the way to the tree canopy. So the strategy for our garden is to have a broad diversity of plants mimicking a small slice of deciduous woodland, with a mix of trees, shrubs, and herbaceous plants including perennials, ferns and sedges.
Having a good mix like this accommodates a wide variety of interesting residents, including butterflies, birds, bees, moths, spiders, wasps, flower flies, ants, tree crickets, katydids, and others I’m still trying to identify. A good mix of critters means that they’ll all help keep each other in balance, with no one species dominating, and no need for chemical intervention.
During the winter months we enjoy the silhouettes of the trees, shrubs and spent perennials, and the birds that visit them. In March the transition to spring begins, with buds swelling and leaves beginning to emerge from the soil. By April the first flowers appear, at multiple layers in the garden.
Before the trees unfold their leaves, among the first blossoms to appear are those of Red Maple, Northern Spicebush, and Golden Ragwort. Although Mourning Cloaks generally prefer sap, I have actually seen them nectaring on Red Maple flowers. Spring Azures are pretty eclectic in their beverage tastes, even sipping from the starburst yellow flowers of Spicebush.
Heartleaf Foamflower, Green and Gold, Creeping Phlox and Canadian Wildginger quickly join the mix, while Virginia Creeper leaves begin to unfurl, adding to the ground cover.
As the days warm in April, violets begin to bloom. We have three well-established species: a white form of Common Blue Violet, the purple Schrank Alpine Violet, and Striped Cream Violet. They are spreading with the aid of ants, who eat the tasty elaiosome attached to violet seeds and then discard the seeds, effectively planting them. Last year a friend gave us a species with interesting lobed leaves, Early Blue Violet. All are available for fritillaries to lay their eggs nearby in late summer so their caterpillars, after spending the winter in leaf litter, can feed on them as both begin to grow in spring.
By late April or early May, Golden Zizia, Spotted Geranium, and Greek Valerian are all in bloom. Black Swallowtails may use Golden Zizia as caterpillar food plants, although they are also very willing to use the parsley and dill we grow in pots on the kitchen patio.
May brings blossoms at all levels of our woodland garden. Tuliptrees flower as high as their canopy, attracting bees with their copious nectar. Flowering Dogwood’s white bracts and Blackhaw Viburnum’s large round clusters of tiny white flowers light up the understory.
The shrub layer is graced with Gray Dogwood, Mountain Laurel, and Virginia Sweetspire. Many Azure butterflies favor dogwood and viburnum flower buds as caterpillar food sources, and will lay their eggs there. Ants protect Azure caterpillars from predators in exchange for the sweet honeydew they excrete.
Leaves of White Baneberry (a.k.a. Doll’s Eyes) and Common Ladyfern, Marginal Woodfern, Christmas and Northern Maidenhair Ferns are now available for perching or basking platforms. The male Zabulon Skipper pictured here is working to attract a mate.
While I watched him, when another butterfly flew by, regardless of species – Red Admirals, anglewings or swallowtails – he chased them away. With mission accomplished, he returned to a horizontal perching platform provided by White Baneberry leaves or the tips of a Christmas Fern frond, both along the edge of the moss path that curves through the garden. They offer the perfect elevation and exposure for the skipper to show himself off to prospective mates.
The secret is to choose plants that are naturally adapted to a woodland environment. They’ll be happy with the soil, moisture, and available light with minimal intervention from you, and no chemical fertilizers. Most of these perennials bloom for about 6-8 weeks, although Green and Gold may bloom throughout the summer if you deadhead. The shrubs usually flower for 2-3 weeks. After a warm winter, blooming may begin weeks earlier than usual. This past January I saw Golden Alexander in bud – a little scary!
So there is plenty of interest in the garden in spring. But what will bloom in the shade of summer and fall? And what butterflies will visit? Stay tuned!
See below for a list of scientific names for the plants featured in this post:
Red Maple (Acer rubrum)
Northern Spicebush (Lindera benzoin)
Golden Ragwort (Packera aurea)
Heartleaf Foamflower (Tiarella cordifolia)
Creeping Phlox (Phlox stolonifera)
Green and Gold (Chrysogonum virginianum)
Canadian Wildginger, Wild Ginger (Asarum canadense)
Common Blue Violet (Viola sororia)
Schrank Alpine Violet, Labrador Violet, American Dog Violet (Viola labradorica)
Striped Cream Violet (Viola striata)
Early Blue Violet (Viola palmata)
Golden Zizia (Zizia aurea)
Spotted Geranium (Geranium maculatum)
Greek Valerian (Polemonium reptans)
Tuliptree (Liriodendron tulipifera)
Flowering Dogwood (Cornus florida)
Blackhaw (Viburnum prunifolium)
Gray Dogwood (Cornus racemosa)
Mountain Laurel (Kalmia latifolia)
Virginia Sweetspire (Itea virginica)
White Baneberry, Doll’s Eyes (Actaea pachypoda)
Common Ladyfern (Athyrium filix-femina)
Christmas Fern (Polystichum acrostichoides)
Marginal Woodfern (Dryopteris marginalis)
Northern Maidenhair Fern (Adiantum pedatum)
This article was also published in the Spring 2013 issue of Butterfly Gardener, a publication of the North American Butterfly Association.