Replacing grass, weeds and moles

Asked March 7, 2019, 1:05 PM EST

We have about 1/2 acre of flat clay soil that is covered with grasses, dandelions, various weeds and gophers and moles. We are on a well and don't want to have to irrigate whatever we replace this mess with. We would like not to have to mow it and the plants would be tall enough to cover the gopher hills. An added bonus would be pollinator friendly. The clay dries out in the summer and is not well drained in the winter. Perennial ground cover is desired and maybe a mixture of plants would have better success. Do you have any suggestions? Thanks.

Benton County Oregon wildflowers and native plants sustainable gardening and landscaping

1 Response

Thanks for your inquiry.

You might want to consider "meadowscaping" your area with native plants that are suited to the soil clay soil conditions. Many of these will attract pollinators and do better without being irrigated in summer (though they may go dormant and not be green like a conventional lawn).

A helpful overview of meadowscaping with detailed instructions for establishing a meadowscape can be found here: https://wmswcd.org/wp-content/uploads/2016/04/Meadowscaping_Publication_Complete_LR.2.pdf

Some good plants to consider for clay soils that are wet in winter but dryer in summer are those listed under the headings "For dryer areas" in this publication. Check out flowers and ground covers: https://extension.oregonstate.edu/gardening/techniques/native-plants-streamside-garden

If you're interested in a more lawn-like appearance - lower growing plants that require some mowing and irrigation but have a more green, uniform look-- consider an eco lawn. Recommended plants and tips for eco lawns are listed here: https://extension.oregonstate.edu/gardening/techniques/ecolawn-less-work-water

Whatever option you choose, the existing grass will compete with what you plant, so consider options to control the grass before you start. The meadowscaping publication linked above has directions for mulching to remove unwanted plants, which might be challenging to use for a half acre site. Some alternatives to consider might include tilling (when soil is dry and well drained - not wet!), irrigating lightly so grasses to resprout, and tilling again to kill grass resprouts before planting. This would be best accomplished in early fall before heavy rains, so clay soil would not form clumps when tilled. If you're open to herbicides, a broad spectrum herbicide applied according to label directions could be an option to reduce grasses before planting. You might need multiple applications to get maximum grass reduction. Whatever option you pick, the goal would be to reduce those water thirsty grasses with their roots that can go down 20+ feet and free up space for your new plantings.

I hope this is helpful and thanks for contacting Ask an Expert.