Utah includes USDA plant hardiness zones 3 to 8. With mountains, deserts, plains and valleys, all with different types of weather and terrain, gardening in Utah is vastly different from one part of the state to another. If you are plagued with clay soil, as much of Utah is, you can successfully garden in such soil conditions, or you can improve the soil to have more flexibility in your garden choices.
Grow plants that tolerate clay soil, such as honeysuckles, willows, laurel and roses. Check the plant's rated USDA plant hardiness zones if you are planting perennials. When you plant in clay soil, dig holes that are twice as large as necessary and break up any large chunks of clay. Next, refill the holes so your plants are planted to the same depth as they were planted in their original containers. Then, add mulch and water your plants.
Choose to amend the soil if you'd like a wider selection of plants suited for Utah, such as peonies, bleeding hearts, alyssum and African daisies.
Till the soil to a depth of about 6 to 8 inches. Rent a rototiller if you don't have one. Tilling Utah clay soil with a hoe or garden rake can be very labor-intensive.
Incorporate 2 to 3 inches of both builders' sand (which is coarse, not fine) and coarse organic matter, such as compost. According to the Puyallup Research and Extension Center at Washington State University, to really improve clay soil, you need to add both coarse sand and coarse organic matter at a rate that your new soil contains half clay and half the new matter.
Water the newly improved soil with about an inch of water to settle it. Wait a week to plant your plants to give the soil time to settle so you can accurately plant your plants to their proper depths.
Plant plants appropriate for Utah's climate, but consider your environment as well. You now have soil that drains well and if you live in an area of Utah that often experiences droughts and you cannot supplement waterings--perhaps because of water restrictions--choose plants that are drought-resistant, such as silver mounds, purple coneflowers and black-eyed Susans.
Mulch your plants in the spring and fall with 2 to 3 inches of organic mulch. This will help conserve water during the hot Utah days and keep the soil warm in the colder zones in the winter months. Organic mulch will also decompose and will further improve the soil over time. Do this whether you improve the soil or not.
Water your plants weekly if you amended your soil (an inch will suffice for most plants). If you chose drought-resistant plants or did not amend your clay soil, you will water less often, such as once every three to four weeks.