How To Plant Potatoes Well

Potatoes are easy to grow in holes, trenches, under mulch or landscape fabric, or in containers. Grow potatoes in full sun and well-drained soil or mulch.

Plant potatoes when the soil temperature is at least 50°F. Potatoes grow best when the air temperature is between 60 and 65°F.

Grow potatoes from seed potatoes—small tubers grown especially for planting to produce a crop. Keep plants evenly moist as tubers develop and enlarge.

New or baby potatoes are harvested early in the season 75 to 90 days after planting. Main-crop or mature potatoes require 135 to 150 days to harvest.

The traditional time to plant potatoes is in spring as soon as the soil can be worked, about two to four weeks before the last expected frost. Spring planted potatoes grow best in beds covered with plastic or raised beds that warm quickly. Keep beds covered with compost or straw until plants emerge. Protect newly emerged plants from frost and insects by covering the planting bed with a floating row cover.

Protect growing potato tubers from light, fluctuations in temperature, pests, and injury by keeping them covered as they grow. Use soil, compost, mulch, hay, straw, or landscape fabric to keep tubers covered. As potatoes grow, tubers push upwards and are easily exposed to light. Tubers exposed to light turn green and contain a chemical called solanine which can be poisonous.

Trench planting is the traditional method for growing potatoes. Dig a trench or hole 4 to 6 inches deep, put the seed potatoes in place one foot apart, and backfill with 2 inches of soil. When the plant grows to 6 inches tall, add soil to cover all but the top leaves; fill the hole or trench as the foliage grows on and continue to hill up loose soil around the plants.

Seed potatoes can be set on the surface of a planting bed and covered with soil; as with trenching, continue to hill up or mound soil above the tubers. At the end of the season, the plants will be covered by a low mound of soil.

Potatoes can be grown across the surface of a planting bed by simply covering seed potatoes with mulch. This method requires no digging.

Loosen a few inches of soil across the planting bed then lay seed potatoes on the soil cut side down about one foot apart. Each seed potato should have two or three eyes. Cover the seed potatoes with one foot of mulch—shredded leaves, leaf mold, or clean hay or straw.

When shoots and leaves have emerged from the mulch and grown about 6 inches, add more mulch—enough to cover all but the top most leaves. Repeat this process. After several weeks, begin to check under the mulch periodically for developing tubers. The mulch should always be several inches thick over the tubers keeping tubers from turning green.

Mulch, unlike soil, is not rich in nutrients so the yield may be less. Feed mulch grown potatoes with fish emulsion— after sprouts emerge and again just before plants flower.

To harvest new or mature potatoes, lift the mulch and take what you need; be sure to recover still growing tubers so that they do not green.

Potatoes can be grown under black landscape fabric with almost no effort. Place seed potatoes on the planting bed one foot apart then place black landscape fabric over the planting bed. The black fabric will exclude light as though the tubers were underground. As plants emerge they will begin to push up the fabric; cut slits in the fabric to allow the plants to grow up. Make sure that as plants grow, tubers are kept under the fabric and not exposed to sunlight. To harvest potatoes enlarge the slit or roll back the fabric to expose the tubers.