This post was originally published May 2016.
Derby day is behind us, which means one thing in Kentucky: It’s time to get outside and garden! Many people are interested in landscaping to attract birds, butterflies, and other wildlife to their backyards, but may be unsure about where to begin.
In Gardening for the Birds, Thomas G. Barnes offers tips that will help even novice gardeners use native plants to create attractive, low-maintenance habitat gardens for wildlife. Such landscaping, Barnes notes, can be as simple or as complex as the homeowner wants to make it. Today we’re sharing an excerpt from this classic book that outlines five simple steps for designing and planting a native wildflower garden:
Planning Your Garden
1. Determine the environmental conditions of your planting site. To reap all of the conservation benefits of using native plants in the landscape, rely on species adapted to the environmental conditions of the planting site rather than trying to adapt the site to a set of pre-selected plants. You reduce labor and costs of site preparation, have much greater success, and minimize post-planting maintenance. As Ken Druse states in The Natural Habitat Garden, “Don’t fight the site.”
Depending on past land use, soils may need to be restored to make them capable of supporting native plants. Soils are often compacted and lack topsoil following construction activities. If the soil is inadequate, loosen it to improve aeration and drainage properties and replace lost nutrients before planting. Sites currently supporting landscape plants of any kind are probably capable of supporting native plants with little additional preparation.
Plan for a Butterfly Garden:
2. Choose an appropriate natural community as a landscape model. A natural community is an assemblage of plants and animals that co-exist in nature because they have similar requirements for natural resources and are able to compete successfully with each other for those resources. A natural community is usually characterized by its plant and animal species. We can predict the type of natural community that will develop on a site based on climate, soils, topography, and other environmental conditions. Natural communities are excellent landscape models because they are self-sustaining and support a diversity of plant and animal species. Once you have defined the environmental conditions of your planting site, determine the natural community type that occurs under similar conditions in your region of Kentucky. Plants characteristic of that community will grow well in your habitat garden.
Although many types of natural communities exist in Kentucky, they can be classified generally as upland or lowland forests or prairies. Most of the Kentucky landscape originally was forested, and, in the absence of grazing and fire, most sites eventually regenerate to forest. Various management techniques such as mowing, grazing, or burning are needed to maintain open landscapes in most of Kentucky. For landscaping purposes, it is helpful to know the light and soil conditions common to forest and prairie communities.
In a natural forest, overstory trees create a canopy that filters the amount of sunlight reaching the forest floor. The leaf canopy creates conditions of dappled shade and sunlight. In some forests, little direct sunlight reaches the forest floor. Shrubs and herbaceous plants that grow in a forest are adapted to varying levels of shade. In a deciduous forest, the floor receives full sun throughout the spring until the leaf canopy develops. This sun promotes new spring growth of ferns and wildflowers. A backyard with mature shade trees creates conditions of shade similar to that of a natural forest. In contrast, the shade on the north side of a building is a dense shade not desirable for most plants, but many native forest shrubs and wildflowers do fine in dense shade if drainage and air circulation are adequate.
Forest soils generally have a high organic content. Leaves, bark, stems, and other plant debris litter the forest floor each year and begin the process of decomposition that builds the forest soils. This process can be replicated in the backyard by mulching with leaf litter and amending the soil with compost, peat, or other organic materials.
In contrast to the forest, a prairie is an open grassland characterized by a high diversity of grass and wildflower species and few tree or shrub species. It is a more extreme environment than a forest because it receives full exposure to the sun and elements. Most prairie plants tolerate a wide range of moisture conditions and are drought-tolerant. The bluestem prairie, which once covered millions of acres in Kentucky, ranged from wet to dry. In a wet prairie, plants are generally tolerant of saturated soil conditions (soil at maximum water-holding capacity), but most are also able to withstand dry periods of varying lengths. In dry prairies or glades, plants are tolerant of well drained to excessively well drained soil conditions. These plants are highly drought-tolerant and excellent choices for xeriscaping (landscaping to conserve water).
Prairie soils vary greatly from one community to the next. Most prairie plants are extremely efficient at utilizing available soil nutrients and do not require highly fertile soils. Some prairie plants grow in shallow, rocky soils, but getting them established in such soils can be difficult.
It is critical that you minimize competition from cultivated grasses and agricultural weeds. Most prairie plants thrive in a good garden soil if competition is minimized. Fertilizing with nitrogen only promotes the growth of annual invasive weeds. If there is a severe deficiency of phosphorus or potassium or if the soil needs liming (as determined by a soil test), apply these fertilizers following soil test recommendations. If a site supports a lawn or a healthy growth of weeds, it should be adequate for growing most prairie plants.
If your site contains overstory trees and is shady much of the day, model your garden after a forest community. If the site receives six or more hours of direct sun, particularly during the hottest time of the day (late morning to late afternoon), a prairie community is a better model. If the site stays wet much of the growing season or is prone to seasonal flooding, a lowland community is appropriate. The savanna community (or barrens on drier upland sites) might be a suitable model for large sites or sites with some shade and some sun. A savanna is an open meadow with scattered individual trees or groves of trees and is very park-like in appearance.
It is possible to plant trees to create shadier conditions or remove trees to create sunnier conditions. Creating wooded conditions is a worthwhile, if long-term, process of great value to wildlife. Establishment of trees might be expensive, but maintenance is minimal. Any healthy, native tree should be considered a valuable landscape and wildlife asset. A single mature (30-foot-tall) hemlock tree purchased from a nursery can cost $12,000. A 60-year-old white oak is worth tens of thousands of dollars. Unless a tree is severely diseased or weedy and invasive (tree of heaven, for example), removal is not recommended. It is better to maintain existing trees whenever possible and convert already sunny sites to native prairie plants.
3. Create plant menus for each habitat garden. Create a menu of plant species for each landscape. Native plant nursery catalogs provide availability and cost information, and many contain detailed habitat and cultivation information for the species they offer. Consult a field guide or botanical book for more information and to see drawings or photographs of the species you intend to establish.
A plant menu can be a simple list of plant species but has more value if composed as a matrix containing functional and physical attributes for each species. Such information is crucial when you begin the landscape design process. Include plant type, sun tolerance, soil moisture tolerance, aesthetic characteristics (flowers and fruits, bark, form, autumn color), period of bloom, wildlife value, and potential uses (shade, evergreen screen, erosion control).
4. Use diverse plants. Most wildflowers and other native plants have distinct flowering and fruiting periods that last a few weeks, rarely longer. For lots of color as well as nectar, fruit, and nut production, use a diversity of plant types (trees, shrubs, ground covers) and species. Diverse plant types provide assorted habitat elements that can be used by a variety of wildlife species. Select various species that bloom during spring, summer, and fall and plants that hold their fruits into winter. Native grasses provide good color in the garden in autumn and excellent wildlife cover in winter. In Kentucky, most forest wildflowers are spring-blooming, so add later-blooming species of woodland phlox, lobelia, aster, and goldenrod. Most prairie plants do not bloom until late spring. Some of the earliest bloomers include coreopsis, wood mint, sundrops, and downy phlox. Offering areas of both forest and prairie in your landscape provides year-round food and cover for wildlife.
5. Use clustering for enhanced beauty and wildlife value. Some wildflowers have large, showy flowers and can be used individually or in small groups with dramatic effect. Many wildflowers, however, are most attractive when planted in species clusters, or drifts. In nature, the most striking wildflower displays result from a tendency for species to grow in clumps. This tendency is influenced in large part by their methods of self-propagation and seed dispersal. Even in a garden, each species rearranges itself over time according to its own propagation patterns. One wild columbine is pretty for close-up viewing beneath a tree, but a drift of columbines in a wildflower border creates a solid block of color and texture visible from a distance. Planting species in clusters of several to dozens lends a natural quality and beauty to the landscape.
Clustering is also beneficial to wildlife. With the maximum amount of food in a single location, animals expend minimal energy to acquire it. Imagine the energy you would use if you had to go to one restaurant for an appetizer, another for the main course, and a third for coffee and dessert! Now think about a hummingbird—a bird with an extremely high metabolic rate—having to fly from one neighborhood to another just to find enough food for lunch. By planting large clusters of favorite foods (phlox, columbine, bee balm, cardinal flower) and hanging an artificial feeder or two you can feed many hummers with little effort on their part.
Thomas G. Barnes (1958–2014) was extension professor of forestry and wildlife specialist at the University of Kentucky. He is the author of Gardening for the Birds, Kentucky’s Last Great Places, Wildflowers and Ferns of Kentucky, and Rare Wildflowers of Kentucky.