A prairie restoration and a prairie garden are not exactly the same thing. The essence of the original prairie was its expanse - a waving sea of grassland extending as far as the horizon. Few gardeners have the acreage to devote to a completely restored prairie ecosystem, complete with bison herds.
A prairie garden is not just a microcosm of a prairie. At its best, it can be a showcase for the variety of the vegetation and wildflowers native to the prairie. Your garden can have a wider variety of plants than might be found in the same area of a natural prairie, and a selection chosen for continuous bloom throughout the year.
An established prairie garden usually requires minimal care - no fertilization, spraying or watering. It is particularly suitable in locations where water conservation is a problem. A prairie garden will support many species of native birds and other animals, and it can do double duty as a butterfly garden.Just about anyone can plant a garden by putting in ornamental grasses and a selection of other plants commonly growing on the prairies. A prairie restoration garden is a more demanding operation, as it involves selecting only those plants originally native to a given area - preferably an area within the prairie's natural range. Both can be attractive and rewarding projects.
The first step in making a prairie garden is selecting and evaluating the site to see what kind of prairie would naturally grow there. Prairie plants evolved in a region of temperature extremes, where the summers are scorching and the winters are frigid, where annual rainfall is 35 inches or less - diminishing from east to west. There are three general zones: thex tallgrass prairie zone stretches in a rough triangle from the tip of Lake Michigan to about the 100th meridian, where it is replaced as the region grows more arid by shorter grasses, the midgrass and shortgrass prairies. Within these zones, there are wet prairies, dry prairies, and mesic prairies, midway between wet and dry.
Know what your growing conditions are and select the plants best suited for them. Above all, whatever the other conditions, prairie plants require full sunlight. For a typical prairie garden, choose a location out in the open, away from trees, and well-drained.
A prairie, above all, is a grassland. As much as 80% of a prairie's natural vegetation might be grasses. For a garden, a larger proportion of other plants, particularly flowering plants, will probably be considered desirable, but a prairie must have grasses to be a prairie.
Not just any grass will do, and particularly not common lawn grass, which is one of the most vexing invasive weeds for a prairie garden. The typical prairie grass is a clumping grass, much like the ornamental grasses that are so popular now as accent plants in gardens and lawns. Many of these ornamentals can serve to give the general look of a prairie, particularly in zones where the true prairie grasses do not thrive, but for a restoration garden, you will want to select your region's natives.
My own location in NE Illinois is the most easterly region of the tallgrass prairie, where the climax grasses are the magnificent Big Bluestem and Indiangrass, which give the tallgrass prairie its name. Under good conditions, these grasses can grow as high as eight feet.
Besides grasses, you will want to plan for a good selection of flowering plants or forbs. A well-planned prairie garden will be in bloom from spring through the end of fall, as one flowering succeeds another. Be sure to include such plants as milkweed, bergamot, and goldenrod to attract the butterflies and bees from one season to the next.
Most prairie plants are perennials. They can be planted as transplants or seeds, but be careful about cut-rate "instant prairie" packaged seeds, which may contain inferior or non-native varieties and too many annuals. For a restoration garden, seeds or plants should be gathered from your region, but be sure not to go around collecting seeds and digging up plants where they may be managed or protected; the law frowns on this. There are many local resources that can help you obtain plants native to your area.
For a very large area, seeds are probably the only practical alternative. Seeds can be planted in either spring or fall. Seedlings may need watering until established, but usually not thereafter. Most of these plants are adapted to dry conditions with low rainfall.
For a garden in a smaller area, transplants are probably the better choice. Some prairie plants can take a long time to become established from seed, and it is not always easy to recognize the seedlings and distinguish them from weeds. Many of these plants propagate naturally by rhizomes or other vegetative means.
Before you plant, you should prepare the site of your garden by killing off any existing vegetation, including weed seeds that might lie unsprouted in the soil. This is particularly important if you are going to seed your garden, so that the new prairie seedlings are not choked out by weeds. This can be done by repeated deep tilling, by the use of herbicides such as Round-Up, or by smothering the existing plants with black plastic or layers of newspaper.
When planning your garden, be sure to take into account the great height to which some of these plants can grow. The taller specimens should be placed in the back if the garden is a border, or in the center. Flowers like liatris, bergamot, asters and goldenrod should be planted together in a mass for best effect, rather than scattered, one here and one there. Consider also that many of these will spread, and leave room.
Many native prairie wildflowers have become popular garden plants and are widely available at local nurseries and through catalogs. But you should also include some less well-known varieties, such as Compass Plant [Silphium laciniatum] or Lead Plant [Amorpha canescans], if you have room and you can find specimens. These will make your prairie garden a little more prairie-like.
Additional installments in this series of articles will showcase the succession of growth in a restored tallgrass prairie, as a guide to planning a prairie garden
An partial list of prairie plants with time of flowering and height:
- Andropogon gerardii - Big Bluestem Aug. - Sept. tall
- Bouteloua curtipendula - Sideoats Grama July - Sept. short
- Panicum virgatum - Switchgrass Aug -Sept tall
- Schizachyrium scoparium - Little Bluestem Sept. mid
- Sorghastrum nutans - Indiangrass Aug - Sept. tall
- Asclepias tuberosa - Butterfly Weed July - Aug. mid
- Aster laevis - Smooth Blue Aster Aug - Oct short
- Baptisia australis Blue False Indigo June - July tall
- Coreopsis palmata - Prairie Coreopsis June - July mid
- Echinacea purpurea - Purple Coneflower June - Sept. mid
- Helianthus rigidus - Prairie Sunflower Aug - Sept tall
- Liatris pycnostachya - Meadow Blazing Star Aug. - Sept. mid
- Lithospermum canescens - Hairy Puccoon May - June short
- Lupinus perennis) - Wild Lupine May - June short
- Monarda fistulosa - Wild Bergamot [Beebalm] July- Aug mid
- Penstemon grandiflorus - Large Flowered Beardtongue May - June mid
- Phlox pilosa - Prairie Phlox May - July short
- Rudbeckia hirta - Black-eyed Susan July - Aug. mid
- Solidago Rigida - Rigid Goldenrod Aug - Sept tall
- Sisyrinchium albidum - Blue-eyed Grass May - June short
Photo credits: Plexippus, GoNative, Equilibrium
References: Kirt, Russell R., Prairie Plants of the Midwest. Stipes Publishing LLC, Champaign, IL, 1995