Red potatoes are popular for home gardens due to their thin skin and potential for an earlier harvest than many other varieties. Cultivars like ‘Red Norland’ or ‘Red Pontiac’ offer a waxy texture ideal for boiling and salads. Successful cultivation requires careful site preparation, precise planting, consistent maintenance, and understanding the two distinct harvest periods. This guide covers the necessary steps to maximize your yield, from site selection to the final curing process.
Site and Soil Preparation
Red potatoes require a minimum of six hours of direct sunlight daily. They thrive best in loose, deep, and well-drained soil, ideally a sandy loam. This soil type allows tubers to expand easily and prevents waterlogging, which can lead to rot and disease. Heavy clay soils should be avoided as they can result in misshapen tubers and increased disease risk.
Red potatoes perform best in slightly acidic soil, targeting a pH range between 5.0 and 6.0. This range helps suppress common scab, a soil-borne disease. Before planting, incorporate significant amounts of organic matter, such as well-aged compost or decomposed manure. This amendment improves soil structure and provides a slow-release source of nutrients for the heavy-feeding potato plants.
The initial step is sourcing certified, disease-free seed potatoes, not grocery store potatoes, which are often treated to inhibit sprouting. Small tubers (1 to 2 inches) can be planted whole. Larger tubers should be cut into block-shaped pieces, roughly the size of a chicken egg, ensuring each piece has at least one or two ‘eyes.’ While cut pieces can be planted immediately, allowing them to sit for 24 to 48 hours to form a protective callous reduces the chance of rotting in cool, damp soil.
Planting and Hilling Techniques
Planting should occur in early spring, two to four weeks before the average last frost date, once the soil temperature is consistently above 45°F. Place seed pieces four to six inches deep and space them 10 to 12 inches apart within the rows. Rows should be spaced 30 to 36 inches apart to allow room for hilling. Planting the seed pieces with the cut side facing down can aid in proper growth orientation.
Consistent moisture is important, especially once plants begin to flower and tubers start to form. Plants require one to two inches of water per week, depending on soil type and weather, to ensure continuous, even growth. Deep, infrequent watering is preferable to shallow sprinkling, which encourages only surface root growth.
The practice of “hilling” should begin when emerging shoots are six to eight inches tall. Hilling involves mounding loose soil or a soil/compost mix around the base of the plant, covering all but the top few inches of foliage. New tubers develop on underground stems called stolons, which grow from the buried portion of the main plant stem.
Hilling primarily protects developing tubers from sunlight exposure. Sunlight triggers the production of chlorophyll and the toxic alkaloid solanine, causing potatoes to turn green and become inedible. Continuously mounding the soil extends the underground stem, encouraging the formation of more stolons and a larger yield. Repeat this process every two to three weeks, or whenever new growth reaches six to eight inches, until the hills are robust and 10 to 12 inches tall.
Harvesting and Curing
Red potatoes offer two distinct harvest opportunities, starting with “new potatoes.” These smaller tubers can be dug approximately seven to eight weeks after planting, often when the plants begin to flower. New potatoes have thin, delicate skin and a waxy texture. They can be gently harvested from the sides of the hills without disturbing the entire plant, allowing the remaining tubers to continue maturing.
For a full harvest of mature, storage-ready red potatoes, wait until the foliage naturally yellows and dies back, signaling the end of the growing cycle. After the vines have completely died back, leave the tubers in the ground for an additional two weeks. This allows the skin to thicken and “set,” significantly improving storage potential. Harvest on a dry, sunny day using a digging fork, starting several inches away from the main stem to avoid puncturing the tubers.
After harvesting, potatoes must undergo curing to heal minor surface wounds and toughen the skin. Spread the freshly dug tubers in a single layer in a dark, well-ventilated space for seven to ten days. Maintain high humidity (85 to 95 percent) and a temperature between 45°F and 60°F. Once cured, store the tubers in a dark environment with high humidity, ideally between 40°F and 45°F. This prevents shriveling and delays sprouting.