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Erna Gunther Ethnobotanic Garden at the Burke Museum, U.W. campus
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Native Plant Gardening
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| Native plants are booming in popularity. Nurseries can actually stay in business selling natives only. Home gardeners and professionals buy natives for any degree of project from local ravine tree plantings to revegetating vast wetland acreage. A passionate sense of environmental stewardship, as well as government decrees, drive the native plant movement. Don't like mowing your lawn? Go native. Don't like spraying poison chemicals? Go native. Want more birds? Go native. Sick of gaudy foreign bimbos and voluptuous hybrids with giant neon-colored flowers? Go native. |
| Alas, along with the sensible and commendable advantages we can obtain by planting natives, there is also danger. A few examples illustrate this contention. First, the term "native" is used differently by people. Its precise meaning and context need to be clear for the ideal plan to work -- regardless where or when undertaken. The predominant native plant cover of the lowland Puget Sound region wherein most of us live, has well known, common native species such as sword fern, Oregon grape and salal. But for us lowland dwellers to call "native" plants from the Cascades and Olympics, or coastal Washington or eastern Washington -- is academic only -- such plants are not our natives; they are from very different habitats. Saltwater and freshwater both have fish, and Puget Sound and Lake Washington have close proximity -- but few fish go from one water to the other. |
| Native plants are characterized by their adaptability to certain habitats. Hence, a woodland plant community, a waterside one, meadow, saltwater tide marsh, etc. -- each hosts unique plants. True, a few plants can thrive in diverse habitats: bracken fern for example. If you live on a bluff, exposed to wind and much sun, your native plant mix will differ from that of a nearby resident who lives in a low, sheltered place, such as a ravine. Hikers know well how just a small distance can reveal dramatic changes in plant communities. |
| To have, then, a "native garden" plant collection ideally tailored for your land, requires intimate awareness of what plants grow in your habitat. Once you make a list of all the plants suited to your site, then you need to single-out the best for your desires. You must decide how many of each kind to aim for. Maybe you'll broadcast seeds and let come what may. If you buy containerized plants, you risk thereby introducing pathogens such as soil-borne fungi or European snails. If you buy plants, try to find out whether they are raised from seed, or vegetatively. Seedlings usually offer genetic diversity, a good thing to strive for in a native garden. Cloned plants on the other hand are not usually good choices except where uniformity is sought, as in formal landscape effects with prescribed maintenance. |
| A plant's native range as the map shows, may include your property -- but if your property doesn't have the suitable habitat, the species may fail to grow if planted. For example, it may need humus-rich soil, much moisture, and shade, while your property has gravelly soil, poor in organic matter, dry, and exposed to the sun. Hence, a plant from Italy may flourish in your site, unlike the native woodland orchid you may desire. Study which native plants will do best in your property, and try to get them established by that course nearest in approach to Nature's own way. Native plants don't require irrigation systems, spraying, pruning, etc. Right? Well, if you want a wilderness that's true, but if you want a native plant garden you must work, at least somewhat: gardens need gardeners. |
| Exactly how you "install" your native plantings is open to a wide range of possibilities. Allow -- for the sake of making a point -- a comparison between two extremes. The first project involves a huge amount of land, and includes grading, filling, road-building, sewer lines, and the like. After the "hardscape" is done, planting begins. There is an irrigation system, imported topsoil and mulch, fertilizers, and a maintenance crew. Thousands of containerized plants are purchased and planted. The contractor obtains the plants from any nursery that has them, and doesn't know or care whether the plants were dug wild, cloned, raised from seed, or where their progenitors originally grew. In brief, it is a standard landscape contractor operation, differing solely in that it aims to use natives only. As with ordinary landscape installation projects, however, where true natives are unavailable in the sizes or quantities desired, non-native "substitutes" are accepted. Hence, non-native pussy willows, serviceberries, roses and whatnot, are obtained and planted. The supposition is that such a landscape is more ecologically desirable than would be an otherwise similar undertaking using plants without regard to their native land. Whether such a landscape is more or less attractive to humans, or costs more or less, are issues of secondary concern. |
| So much for the big project example. On the other hand, imagine a Seattleite whose yard lies adjacent to a city park. The park is largely wild, with native and naturalized vegetation. The homeowner wants a few choice non-native ornamental plants in front of the house, with the side and back yard full of plants that are native, and blend superbly into the park. So she rips out her lawn, the rhododendrons, the junipers, the weeds, and uncovers bare soil -- her blank slate. Then, taking a cue from the nearby wild vegetation, she loosens her soil, ærates it, decompacts it, and mulches it with fallen leaves, twigs, and so forth from maples and alders in the park. She knows that if she doesn't cover the bare soil she'll be faced with many seedlings, erosion from rain, and perhaps a muddy mess. As the mulch of leaf matter protects the soil, she scouts the park, considering what kinds of native wild plants she thinks will be best suited to her yard. |
| She knows a diverse mix is needed, to both look natural and be insurance for success. She doesn't want a huge tree, but knows some kind of small trees or large shrubs seem ideal. Since her soil is poor, and her patience limited, she chooses a pussy willow, since it grows rapidly. She knows no nurseries selling seedling pussy willows, and she also knows the trees are raised easily from cuttings. So she decides to go looking for seedlings she can transplant. She has no luck in the woods, for it is too shady. But at the edge of the woods, several mature specimens grow, and their seedlings come up as weeds in a neighbor's irrigated garden beds. She is assured "dig all you want; thank-you." |
| She brings home three, plants them, and proceeds to gradually fill in her yard with shrubs such as red elderberry, red-flower currant, Oregon grape, salal, snowberry, and wild rose. She variously takes cuttings, seedlings or root divisions of these. For a groundcover layer she chooses sword fern, deer fern, mosses and the like. On a trellis/arbor she plants the native orange honeysuckle vine. She also wants mosses, lichens, fungi and microorganisms, so judiciously collects some topsoil to scatter about the base of her plants, as a sort of inoculant/seed-source. In addition, she broadcasts seeds collected from her favorite wildflowers, trusting some will grow: trillium, bleeding heart, vanilla leaf, false Solomon's seal, sweet cicely, fringecups. |
| She doesn't buy a thing. In the eyes of the law, everything she takes -- divisions, seedlings, cuttings, seeds, or even fallen leaves and soil -- is "stolen." The misdemeanor is in taking or "destroying" public property. From her point of view, she is augmenting or enriching the native plant community by bringing it back into her erstwhile barren yard. Her joy of learning and implementing the plan is great. Each year more plants and wildlife fill her yard. She does minimal watering the first summer, weeds-out dandelions and other non-natives, but otherwise lets nature take its course. When plants die she chops them into pieces and lets them serve as mulch. When strong plants grow out of bounds she prunes them back. She creates a true minimally managed native plant garden. |
| A literal interpretation of the law would make it illegal for a person to pick blackberries in the park, or to collect leaves and pine cones for decorations. What our imaginary houseowner did, was the best approach ecologically to revegetate her land. If she had instead bought plants at nurseries, she might've thereby brought in unintentional fungal pathogens, snail eggs, weed seeds, etc. Her purchased native plants might've been raised from plants hundreds of miles away, and thus had different genes. If she had done the job as would the typical landscape contractor, she would've hauled in a truckload of mulch or artificial topsoil to plant in. Again, God only knows the microorganisms, seeds, fungal spores, etc., in such loads. |
| Since the ideal scenario is unattainable usually, especially because of practical constraints such as lack of enough time, or impatient significant others, here is a list of 13 pointers and tenents worth considering before doing a major native plant project. |
| 1. Seed-grown plants are better than vegetatively propagated plants. |
| 2. Seeds should come from more than one parent plant, rather than just one. But if from just one plant, at least it should've cross-pollinated with other individuals. |
| 3. Seedlings (or seeds) used should come from as close to the planting site as possible. |
| 4. Maximum diversity of plants should be aimed at. In nature there is tremendously more, for example, than a tree, a shrub and a groundcover (as planted landscapes commonly feature). |
| 5. Use species adapted to your conditions, rather than try changing your natural conditions to suit those plants you desire. |
| 6. No irrigation system; water only as needed to get the plants established. |
| 7. Eliminate invasive non-native usurper species before they become overwhelming. This is a continual process rather than a one-time extermination. Sort of like bathing regularly. |
| 8. Allow and adjust to evolution. Just as ordinary gardens are not static, but evolve continually as plantings mature, so it is with native gardens. The pioneer stage plantings you undertake, may ultimately become "old-growth forest." Understand what is happening over the years, and decide whether your actions should help or hinder the natural process. |
| 9. Be cautious with your soil. Intensively working the soil, adding organic matter in bulk annually, is farming -- not nature's usual procedure. If you live in a floodplain it may be. Otherwise, recall that nature has native plants which will grow on every kind of soil. If you choose to amend or change your soil, be cautious about importing non-native, nondesirable elements. Better to stick with sand, sawdust, peat or some sterile mix. |
| 10. Avoid treated, stained or even painted surfaces. For the sake of microorganisms and natural fungal bodies in the intricate web of life, use only natural wood, stone, brick or concrete. Leaching from poisonous preservatives harms life in the soil. |
| 11. Meadows need burning. Otherwise shrubs and trees will reassert the forest. You may need to do this once every few years. Mowing is no substitute. Mowing and livestock grazing favor the toughest, weediest grasses and other plants, most of which are non-native. Minimize mowing or don't do it at all. |
| 12. Wetlands need extra caution. Polluting water is very easy. The habitat is fragile and other than suppressing non-native weedy species your work should be minimal. Add seeds of valuable but rare natives and hope they manage to grow. |
13. Consider the big picture; the long run. A non-native plant can be more valuable ecologically than a native one. For example, if you own a 100 year old apple tree, all mossy and lichen-covered, and think to help the environment by chopping it into firewood and replacing it with a seedling native crabapple -- think again. In the final analysis, whether your property is composed of native or non-native plantings is only one factor of its environmental value. A non-native collection of 500 different kinds of plants, organically grown, an oasis for insects and wildlife, is better than a natives-only garden the same size yet with few plants and less biodiversity. To slavishly try copying wild nature outside your dwellings is not necessarily or usually a practical endeavor. You can do as much good -- or more -- and less laboriously, with more fun, to create a healthy ecosystem, beautiful to you, valuable to natives and an inspiration to others.
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