Prairie plants grow best in full sun and in open spaces. When selecting a site, look for areas with the maximum sun exposure with minimal root competition from trees. Ash, basswood, and maple trees provide more competition for prairie plants because they have many surface roots which compete for water and nutrients. Prairie plants often are more compatible with bur or white oak.

Knowing your soil type and surface drainage is quite important when selecting plants for your prairie. Native prairie soils vary greatly in composition, from dry, gravelly, sandy soils which hold little moisture to silty or heavy clay soils that can hold excessive water. Standing water on a site or water that does not drain from a 1-foot deep hole within 24 hours are indicators of wet and poorly drained soils. Knowing the soil drainage of your site is really more critical than taking a soil test, which is typically done in planting a garden. Although you may have a soil test done, (soil test information is available from your county extension agent or from the University of Minnesota soil testing labs) it is not critical in establishing a successful prairie garden. Understanding the drainage and sun/shade exposure of your site is essential for selecting plants that thrive in your location.

Determine if there are weed ordinances in your city. These ordinances were originally designed to keep yards more attractive and to control the spread of noxious weeds by keeping lawns cut to a certain height.

Ordinances vary from one city to another, so call your city government to find out the specifics on the weed ordinances in your community. Consider using some “elements of care” such as mowed edges, signs, bird houses, edging fences, etc., near your prairie to show the area is meant to be there.

Also, prairies can be fire hazards during dry weather. Leave at least 20 feet of conventional lawn or noncombustible surface between the prairie and buildings or any other combustible items.

The first step in preparing the site for a prairie garden is removing all existing vegetation. If you try to scatter seeds or put young plants into existing vegetation, you will have a very low likelihood of success. Maximize your success by reducing the existing plant competition.

There are three commonly used procedures to establish a prairie in an existing lawn or area of other vegetation. The first method is to put a dark plastic sheet, tarp, or pieces of plywood over the grass for at least two months before you begin planting. This kills the grass, making it much easier to remove, although tough perennial weeds, such as thistles and quackgrass can survive. Once the vegetation is dead, till the area thoroughly. This method often works best when begun in the summer or fall to prepare for a spring planting.

The second procedure is to turn the soil and cultivate the area every few weeks for a complete growing season. Turning the soil brings weed seeds to the surface, and cultivating kills the seeds that have germinated since the soil was last turned. Over time, many of the weed seeds present in the soil will germinate and die. If possible, till to a depth of 12 inches or more and rake the area to create a uniform fine seedbed.

A third method, and probably the most common method of establishment, involves using a nonselective herbicide containing the active ingredient glyphosate, such as Round Up or Kleenup, to kill all existing vegetation. As with all herbicides, be sure to read and follow all label directions. When the vegetation has died in about two weeks, till to a depth of 12 inches or more. If a slit seeder will be used, tilling may be eliminated, and the now dead vegetation can be mowed to a 1 to 2 inches of stubble. This dead mat of roots and sod may actually act as a mulch and prevent excessive weed growth.

Part two of growing a prairie garden will follow next week.

For more information on gardening you can reach me at s.dejaeghere@me.com