Ecology, Mr. Webster tells us, is “concerned with the interrelationship of organisms and their environments.” I call these gardens ecological because they connect one organism—people—to their environment, they link the many pieces of a garden together, and because they can play a role in pre-serving healthy ecosystems.
Ecological gardens also blend many garden styles together, which gives the gardener enough leeway to emphasize the qualities—food, ﬂowers, herbs, crafts, and so on—he or she likes most.
One object of an ecological garden is to restore the natural cycles that have been broken by conventional landscape design and agriculture. Have you ever wondered why a forest or meadow looks perfect and stays nearly disease free with no care at all, while a garden demands arduous hours of labor? In a garden, weeds still pop up like, well, weeds, and every plant seems to be covered in its own set of weird spots and chomping bugs. This happens because most gardens ignore nature’s rules.
Look how gardens differ from natural landscapes. Not only does nature never do just one thing, nature abhors bare soil, large blocks of a single plant type, and vegetation that’s all the same height and root depth. Nature doesn’t till, either—about the only time soil is disturbed in the wild is when a tree topples and its upturned roots churn the earth. Yet our gardens are virtual showcases of all these unnatural methods. Not to mention our broad scale pesticide use and chemical fertilizers.
Each of these unnatural garden techniques was developed for a speciﬁc purpose. Tilling, for example, destroys weeds and pumps air to microbes that, metabolically supercharged, release a flood of nutrients for fast crop growth. These are great short-term boons to plant-growers. But we now know that in the long term, tilling depletes fertility (those revved-up microbes will burn up all the nutrients, then die), causes more disease, and ruins the soil structure with compaction to hardpan and massive erosion as the result.
The bare soil in a typical garden, whether in a freshly tilled plot or between neatly spaced plants, is a perfect habitat for weed seeds. Weeds are simply pioneer plants, molded by millions of years of evolution to quickly cover disturbed, open ground. They’ll do that relentlessly in the bare ground of a garden. Naked earth also washes away with rain, which means we’ll have to do more tilling to ﬂuff the scoured, pounded earth that’s left, and add more fertilizer to replace lost nutrients.
Solid blocks of the same plant variety, though easy to seed and harvest, act as an “all you can eat” sign to insect pests and diseases. Harmful bugs will stuff themselves on this unbroken ﬁeld of abundant food as they make unimpeded hops from plant to plant, and breed to plague proportions.
Each of the conventional techniques cited above arose to solve a speciﬁc problem, but like any single-minded approach, they often don’t combine well with other one-purpose methods, and they miss the big picture. The big picture here, in the typical garden, is not a happy one. Lots of tedious work, no habitat for native or rare species, struggling plants on intensive care, reliance on resource-gobbling poisonous chemicals, and in general, a decline in the garden’s health, yield, and beauty unless we constantly and laboriously intervene. Yet we’ve come to accept all this as part of gardening.
There is another way to garden. Conventional landscapes have torn the web of nature. Important threads are missing. We can restore many of these broken links, and work with nature to lessen our own load, not to mention the cost to the environment. For example, why till and add trainloads of fertilizer, when worms and other soil life, combined with fertility-building plants, will tailor the finest soil possible, with very little work? That’s how nature does it. Then all we need to do is make up for the small amount of nutrients lost to harvest. (Plants are mostly water, plus some carbon from the air. The tiny amounts of minerals they take from the soil can easily be replaced if we use the proper techniques.)
“Let nature do it” also applies to dealing with pests. In a balanced landscape, diseases and insect problems rarely get out of control. That’s because in the diverse, many-specied garden that this book tells how to create, each insect, fungus, bacterium, or potentially invasive plant is surrounded by a natural web of checks and balances. If one species becomes too abundant, its sheer availability makes it a tasty, irresistible food source for something else, which will knock it back to manageable levels. That’s how nature works, and it’s a useful trick for the ecological gardener.
To create a well-balanced garden, we must know something about how nature behaves. Toward that end, this book offers a chapter on ecology for gardeners; many examples of nature’s principles at work are woven throughout the other chapters. When we use nature’s methods—whether for growing vegetables, ﬂowers, or wildlife plants—the garden becomes less work, less prone to problems, and vastly more like the dynamic, vibrant landscapes found in nature. These backyard ecosystems are deeply welcoming both for the wild world and for people, offering food and other products for self-reliance, as well as beauty and inspiration.
BEYOND—WAY BEYOND—NATURAL GARDENING
Some of what you have read so far may sound familiar. The past twenty years have seen the arrival of native plant gardens and landscapes that mimic natural groupings of vegetation, a style usually called natural gardening. Many of these gardens attempt to re-create native plant communities by assembling plants into backyard prairies, woodlands, wetlands, and other wild habitats. So gardening with nature may not be a new idea to some readers.
Ecological gardens also use principles derived from observing and living in wild land, but toward a different end. Natural gardens consist almost exclusively of native plants, and are intended to create and restore habitat for oft-endangered ﬂora and wildlife. They are often described, as Ken Druse puts it in The Natural Habitat Garden, as “essential to the planet’s future.” I support using native plants in the landscape. But natural gardens, offering little for people, will never have more than a tiny effect on environmental damage. Here’s why.
In the United States, all the developed, inhabited land—cities, suburbs, and rural towns, including roads, buildings, yards, and so on—covers only about 6 percent of the nation’s area. You could ﬁll every yard and city park with native plants and not even begin to stanch the loss of native species and habitat.
However, even if developed land in cities and suburbs were packed with natives-only gardens, it would never be wild. Divided into tiny fragments by streets, plastered over with houses and highways, all the streams culverted and run under-ground, ﬁlled with predatory cats and dogs, this is land that has been taken over by humans and our allies, removed from larger ecosystems, and it’s going to stay that way. I don’t deny that if we planted suburbia with natives we might rescue some tiny number of species. But many native species, particularly animals, are incompatible with land occupied by modern people, and require large tracts of unspoiled terrain to survive. Planting suburban yards with natives won’t save them.
Also, the real damage to the environment is done not by the cities and suburbs themselves, but by meeting their needs. We, who live in the developed 6 percent of the land, have an insatiable appetite, and use between 40 and 70 percent of America’s land area (estimates vary widely) to support us. Monocultured farms and industrial forests, livestock grazing, reservoirs, strip and open pit mines, military reservations, and all the other accoutrements of modern civilization consume a huge amount of space, almost none of it native or healthy habitat. Each non-homegrown meal, each trip to the lumberyard, pharmacy, clothing store, or other shop, commissions the conversion of once-native habitat into industrial desert. Every one thousand square feet of house means that about one acre of clearcut forest has the homeowner’s name on it. Certainly, natives should be included wherever they can do the job, but native plant gardens won’t reduce our depredations of wild land very much unless we also lessen our resource use. A native plant garden, while much easier on the environment than a lawn, still means that the owner is causing immense habitat loss elsewhere, out of sight.
Every bit of food, every scrap of lumber, each medicinal herb or other human product that comes from an urban yard means that one less chunk of land outside the cities needs to be denuded of natives and developed for human use. Factory farms and industrial forests—pesticide-laced, monocropped, sterilized of everything but a single species—are far more biologically impoverished than any suburban backyard. But farms and tree plantations are the lands that could truly become wilderness again. Cities and suburbs are already out of the natural loop, so we should strive to make them as useful to people as possible, not simply office parks and bedrooms. Urban land can be incredibly productive. In Switzerland, for example, 70 percent of all lumber comes from community woodlots. Our cities could provide for most human needs, and let cropland and tree farms return to nature.
I’m not talking about converting every backyard to row crops. By gardening ecologically, designing multifunctional landscapes that provide food and other goods for ourselves while creating habitat for other species, we can make our cities truly bloom. But a yard full only of native plants, lacking any for human use, simply means that somewhere else, out of sight, there is a non-native–containing farm and a factory forest, with the environmental destruction they bring, providing for that native-loving suburbanite’s needs. In contrast, a yard planted with carefully chosen exotics (and sure, natives too) will reduce the ecological damage done by the human occupants far more than a native-plant garden. Taking care of ourselves in our own yards means that factory farms and forests can shrink. Somewhere a farmer won’t have to plow quite so close to a creek, saving riparian species that would never live in a suburban lot.