Introduction
Select adapted plants Some Great Basin urban areas in Utah and Nevada exhibit climatic conditions that make it difficult for all but the toughest landscape plants to thrive without providing supplemental water. These areas are found at elevations from 4,000 feet to 6,000 feet in USDA cold-hardiness zones 6 and 7. Soils are often poor and gravelly, containing less than 1 percent organic matter. Soil pH ranges from 6.5 to over 7.5, and some areas have salinity levels that exceed the limits of tolerance for many plants. Precipitation is less than 10 inches per year, and drying winds are persistent much of the time. Many plants under these conditions lose water rapidly due to evaporation from leaf surfaces and from the soil. Rocky, poor soils with little organic matter have little capacity to hold water, causing further stress to landscape plants. Selecting plants that are adapted to such a climate will improve plant survival and achieve aesthetic and functional goals for the landscape.
The list of plants at the end of this publication is a good start for plant selection but is not meant to be all-inclusive. It is simply a compilation of our favorites that have proven successful in our region. A variety of grasses, flowers, shrubs and trees are included to fit many situations. Plants that live more than one growing season are rated for their tolerance to cold using USDA hardiness zones. The plants included in this list are adapted to USDA hardiness zones 6a-7b (-10 degrees to 10 degrees F). To find your zone, refer to their interactive map .
Start with a plan
For year-long landscape interest, create a plan that considers bloom timing and color, including fall color. Be sure to plant so that you have something attractive in your landscape during every season. For example, blanketflower blooms all summer long, but in late fall, the flowers give way to attractive persistent seedheads that lend interest through the winter.
Consider wind direction when determining your landscape plan. Wind may be persistent from the south or southwest during the spring and summer months. Winter wind comes from the north when storms approach. It may be helpful in some locations to provide natural windbreaks such as rocks and trees to offer protection where needed.
Do not overplant your landscape. This is a common mistake made by both homeowners and landscape professionals. It is often done so the landscape achieves a filled-in look right from the start. Unfortunately, plants quickly outgrow their designated spots and have to compete with one another for water and nutrients to survive. Overplanted trees and shrubs may begin to intrude into pedestrian areas or cause damage to property. If you do go for the mature look early, be prepared to remove some plants after a few years to make space for the remaining plants, so they continue to thrive and look attractive as they mature. Place plants in the landscape with wildfire defensible space in mind.
Most of the plants on this list (see link below) are not highly combustible, but any plant can burn if it is not kept well irrigated, properly maintained and free of dead material. The most combustible plants are dry ornamental grasses and evergreen woody plants, such as juniper. Keep these plants at least 30 feet from your home. Shrubs and trees that lose their leaves in the fall can be placed 10 feet to 30 feet from the home if spaced appropriately. Avoid planting anything but flowers, succulents or turfgrass within the first 5 feet of your home.
Amend your soils
Soils in our region are mostly rocky and fast-draining, but some areas may be clayey, which interferes with water infiltration and drainage. Amending your soil prior to planting with a high quality source of organic matter, such as compost, will improve your soil. Well-rotted animal manure is also good, as long as the animals that produced it were fed weed-free forage. Amend soils to a depth of 4 inches to 6 inches prior to planting flowers. Alternately, you can apply compost or manure during the season prior to planting, so it will work itself naturally into your soil. Do not add organic matter to a tree or shrub planting hole unless the soil is very poor. If so, mix one part organic matter to two parts native soil into a wide planting hole, so the roots will grow into the native soil.
Water your plants for drought resistance
Water your landscape plants deeply and on a less frequent basis than your lawn. Deep watering encourages deep rooting, which means your plants will be more resistant to hot, dry conditions and/or reduced soil moisture. Ornamental grass and flower roots reach 12 inches to 18 inches into the soil; shrub and tree roots reach 18 inches to 24 inches. Make sure your irrigation system or your hose remains on your plants long enough to get water to those depths. Set your irrigation system to water twice weekly for ornamental grasses and perennials, and only once every week or two for established shrubs or trees. You may have to irrigate in cycles to prevent run-off.
We have selected plants for this publication that have low water requirements. However, more frequent irrigation is essential for the first year or two to allow plants to become established. You can back off on irrigation frequency as plants mature and establish deep roots. Drip irrigation is suggested as it is the most efficient way to deep-water individual plants and results in less water waste and fewer weeds.
Design your irrigation system to meet the water needs of your plants at their maximum mature size. This makes it easy to size up your system as your plants grow by adding more emitters or replacing them with higher output emitters. You should also pull emitters away from the trunks of trees and shrubs. If you plan to water only during the plant-establishment period, or only during the hottest summer months, your plants will likely reach only the low to middle range of their size capacity.
Finally, do not forget to water your plants during the winter if there is no measurable rain or snow cover. This is especially important for plants with evergreen leaves because they continue to lose water during the winter months. Even though your irrigation system should be drained and winterized by this time, you can apply water once every two to three weeks with a hose or bucket during the warmest part of the day and when soils are not frozen.
For a complete list of our favorite plants use the link below for the full article.
