native plant gardening

Naturally Unnatural

I’ve been reading a thought-provoking book, The Conscientious Gardener : cultivating a garden ethic, by Sarah Hayden Reichard. Every gardener should be aware of the issues Ms. Reichard raises — water use, how we treat our soils, whether to use fertilizer, attitudes toward animals and “pests.” The book is informed by the ideas of Aldo Leopold and proposes a “garden ethic” similar to Leopold’s land ethic.

It includes a chapter on gardening with native plants. I had always assumed that a garden of native plants would be inherently virtuous, pure and green. Native plants would be adapted to the local conditions and so would not require as much care as imported species, so by turning my 50 x 120 foot patch of ground into a miniature Garry oak meadow I would be helping to restore a rare ecosystem. To do that, however, I would have to remove the four rather large non-native trees on the place (an Ailanthus and three Norway maples) and a jumble of other imported species, some introduced by me, others by former occupants and still others that just drifted in. In other words, to make my garden a purely native one I would have to raze the existing plantscape. And even then, there’s still the matter of the house, driveway and surrounding suburbia. Finally, a 50 x 120 foot Garry oak meadow, however commendable, wouldn’t do much to restore the original ecosystem around here, especially as there are indications that the native peoples used fires to maintain it, not possible where there is a permanent burning ban.

Personal preferences and circumstances aside, Reichard suggests that “going native” may not necessarily be the best choice for the conscientious gardener. She points out issues that most gardeners would not be aware of while rushing to stock their gardens with “native plants,” such as a phenomenon called “outbreeding depression,” in which hybridization of different genotypes of a species results in less-fit forms of that species. This means finding out where the plants you intend to purchase come from, something that may not be easy to accomplish. Both wild-collected plants and those cultivated far away and under different conditions than those in your region are not good choices. Rather than creating instant “native plant gardens,” Reichard suggests learning about the native flora of one’s region and getting involved in local efforts to preserve it.

Selecting plants suited to your climate and soil is always the best choice, even if some of them are not “native.” Wetland plants such as red osier dogwood (Cornus stolonifera) or foamflower (Tiarella trifoliata) would be poor choices in my sandy soil, even though they are native to my region. Rugosa roses (Rosa rugosa), many spurges (Euphorbia species) and rose campion (Lychnis coronaria), none of them natives, do well here. Of course there is also the issue of avoiding or at least managing plants with invasive tendencies, especially if you garden near relatively undisturbed native landscapes.

Gardening is inherently unnatural. The gardener always interferes with plants to some extent, if only by managing whatever is growing in a place already, like the native peoples of our region did with the meadows where camas bulbs grew. Gardeners who enter into a true relationship with the land on which they garden, observing and learning about all its inhabitants, necessarily make wiser choices and perhaps do less damage than those with an attitude of dominance. Before we ever stick a spade into the earth (or hire a contractor), we should examine our mental model for a garden and whether it is in harmony with the actual, physical place it is to occupy, or a violation of that place. The conscientious gardener, I think, would seek to befriend the earth rather than subdue it.

In this garden, the unnatural business of leaf management is under way.