How to Grow Potatoes in the High Desert

Plow as soon as most of the winter moisture has drained from the soil and the ground is warm enough to work. Otherwise, plowing muddy soil turns the soil into chunks that require reworking. You can also work the soil with a spade, cultivating the soil to a depth of at least 10 to 12 inches.

Improve the quality and water-retention of soil by adding at least 1 or 2 inches of organic material during plowing. Organic material is especially important in high desert climates where the soil is clay-based or sandy. Apply organic material such as compost or rotted animal waste. If you apply fresh manure, it must be worked into the soil in autumn so the manure has time to decompose before spring.

Purchase certified seed potatoes from a garden center or nursery. Don't attempt to plant grocery store potatoes, which are often treated with materials that prevent sprouting. For best results, purchase seed from potatoes grown in your area, because the potatoes will be well-suited for your particular high desert climate.

Cut the seed potatoes into chunks about 1 to 1 1/2 inches in diameter. Be sure each chunk has at least one eye, which is the beginning of a sprout. You can also use small, whole seed potatoes. Allow the potatoes to dry in a shady spot for one to two days before planting. Otherwise, the cut potatoes may rot.

Create furrows 32 to 36 inches apart, using a garden hoe. Plant the seed potatoes in the furrows, allowing eight to 10 inches between each potato. Cover the potatoes with 2 inches of soil to keep them cool during the hot, dry summer weather common to the high desert. Potatoes planted in shallow soil often form healthy tops but no tubers.

Water the potatoes immediately after planting. Continue to water the plants lightly and frequently every two to three days, keeping the soil moist until growth appears and the potatoes are established.

Water established potatoes deeply to promote long, healthy roots. Saturate the soil to a depth of at least 12 inches, and then allow the top 1 inch of the soil to dry between waterings.

Conserve water in a high desert climate by watering during the morning hours to prevent evaporation through sunlight, heat and wind. Avoid watering in the evening if you use a sprinkler, because chilly high desert nighttime temperatures can may promote disease such as powdery mildew. If possible, install a drip irrigation system, which is more efficient.

Mound the soil over the plants when the plants are 5 to 6 inches tall. Leave 4 to 6 inches of green plant top exposed so the plant has access to sunlight. Continue to mound the soil as needed until the potato plants are 12 to 15 inches tall -- usually three or four times during the season. You can also mound the plants with straw or dry grass clippings, which keeps the soil cool during the heat of summer. Use clean straw that contains no weed seeds.

Harvest new potatoes as desired beginning in midsummer. Dig the remainder of the potatoes when the tops die down in August or September.