Rock gardens in the Midwest
If you’ve always associated rock gardens with desert country or the northlands, maybe it’s time to take a fresh look at their possibilities in Midwestern landscapes.
Rocks are a fundamental part of nature. Whether you choose native varieties or mix in some that come from other places, you’re turning to something that inherently provides contrast to plants — and contrast means interest in the garden. In addition, rocks offer strong aesthetic potential in form, color and texture.
Rock gardens nearly always provide changes in level — again, a sure source of interest. Styles range from formal, with symmetrical forms and layouts, to highly naturalistic — the “look what tumbled down this slope” approach.
A huge range of plants can be used in rock gardens, depending on the usual variables of light, soil type and desired look. Certainly short alpine varieties, characterized by cushion habit and miniature size, are appropriate, as are succulents covering the span from low-growing sedums through big yuccas.
However, those categories do not exhaust the possibilities! Dwarf conifers work beautifully in rock gardens and are perfect choices for gardeners desiring low maintenance requirements. Grasses, with their four-season interest, can be used effectively as the mainstay of rock gardens. In shady areas, woodland plants beginning with spring ephemerals and progressing through ferns, Solomon’s seal, and wild ginger can be complemented by mossy walkways.
In planning a new rock garden, you may choose to use what nature provides. For example, a natural rock outcropping might become the center of your plan. Similarly, existing built feature such as low limestone walls or a rocky dry creek bed could provide the shape and structure for a lovely garden.
Starting from bare ground may be a considerably more daunting project, requiring heavy equipment for hauling in soil and rocks and possibly for excavating to meet your design requirements. For a project on this scale, you would be wise to work with a landscaper who has the experience and expertise to assure excellent results.
While most of us associate rock gardens with dry and light soils, it is entirely possible to establish rock gardens in heavy clay soil. Clay provides a good delivery system for important mineral nutrients and has the structural properties to make an excellent foundation for rock garden construction. The key to success with clay is the selection of plants that will thrive. As usual, working with nature will be more productive than fighting it.
Right now: Plant bareroot trees and shrubs. Soak roots for two hours immediately before planting. Dig a hole at least twice the width of the root system. Depth of the hole should match the distance from trunk flare to bottom of roots.
The trunk flare is the point where the trunk begins to widen as it meets the root system. Do not confuse the trunk flare with a graft union, a crook or bulge that will typically be found one to three inches above the trunk flare in fruit trees and some shade trees.