Growing your own potatoes offers a freshness and variety unmatched by store-bought tubers. This popular and versatile root vegetable is accessible to anyone with a sunny garden spot or container. Home gardeners can choose from a vast spectrum of colors, sizes, and textures, from creamy Yukon Golds to earthy Purple Peruvian varieties. The process of turning a small seed potato into a bountiful harvest is straightforward. This guide provides a comprehensive path from initial preparation to final storage, ensuring a successful and flavorful potato crop.
Preparing for Planting
The initial step for a successful potato harvest is selecting the right planting material. Gardeners should always purchase certified seed potatoes, which are guaranteed to be disease-free and untreated with sprout inhibitors. Planting commercial potatoes risks introducing diseases like viruses or blight that can persist in the soil for years. Seed potatoes are cut into pieces roughly the size of a chicken egg, ensuring each piece contains at least one or two “eyes,” the indentations from which new growth emerges.
Before planting, undertake “chitting” to encourage strong, stubby sprouts. Place the cut seed pieces upright in a tray, eyes facing upward, in a bright, cool, and frost-free location. After four to six weeks, the seed potatoes will develop short, dark green or purple sprouts. Chitting gives the plants a head start, potentially leading to an earlier and larger yield.
Potatoes thrive in well-drained, loose, and sandy loam, requiring careful attention to the soil. They prefer a slightly acidic pH level (5.5 to 6.0) to help prevent common scab disease. Amending the soil with compost or well-aged manure improves structure and provides micronutrients, as potatoes are heavy feeders. A soil test can help tailor necessary amendments, ensuring the plants have the proper nutrients from the start.
Planting Methods and Techniques
Potatoes are planted in early spring once the soil temperature reaches at least 45°F, typically two to four weeks before the last expected frost. The traditional method involves digging a shallow trench, six to eight inches deep, in the prepared soil. Place seed pieces cut-side down, spaced 10 to 12 inches apart, in rows separated by 30 to 36 inches. Initially, cover the seed pieces with only three to four inches of soil, leaving the trench mostly unfilled for later maintenance.
Home gardeners often use alternative methods that save space and simplify harvesting. Planting in containers, such as grow bags or potato towers, works well for small gardens or patios. These methods involve placing a layer of growing medium at the base, planting the seed pieces, and gradually adding more soil or compost as the plant grows. Spacing influences the final yield: closer spacing produces numerous smaller potatoes, while wider spacing results in fewer but larger tubers.
Essential Maintenance During Growth
The most important maintenance task is “hilling,” which involves mounding soil, straw, or compost around the emerging plant stems. Begin hilling when the shoots are six to eight inches tall, pulling the material up until only the top few inches of foliage are exposed. Repeat this process every time the stems grow another six to eight inches, gradually building a substantial mound. The primary purpose of hilling is to prevent developing tubers from being exposed to sunlight, which causes them to turn green and produce the toxic compound solanine.
Hilling also increases potential yield by creating a longer underground stem section (stolon) where new potatoes develop. Consistent watering is paramount, especially once the plants begin to flower, signaling the start of tuber development. Potatoes require one to two inches of water per week; moisture stress during this time can lead to misshapen or hollow tubers. Remain vigilant for common pests like the Colorado potato beetle and fungal diseases such as blight, which can quickly destroy a crop.
Harvesting and Curing Potatoes
Knowing when to harvest depends on the desired size and type of potato, but for long-term storage, the plant must signal its readiness. For mature, main-crop potatoes, the foliage will naturally begin to yellow and die back, usually 90 to 120 days after planting. It is beneficial to stop watering the plants about two weeks before the planned harvest to allow the soil to dry out, which helps the skins to thicken and “set.” Once the tops have completely died back, leave the tubers in the ground for an additional 10 to 14 days to further toughen the skin, which is essential for successful storage.
Harvesting requires a careful approach to avoid piercing or bruising the delicate skin of the tubers. Use a pitchfork or blunt-tined digging fork, starting several inches away from the main stem to prevent accidental damage. Gently lift the plant and loosen the surrounding soil to reveal the potatoes. Brush off any excess dirt rather than washing them, as moisture can encourage rot.
Freshly harvested potatoes need a post-harvest step called curing, which hardens the skin and heals minor abrasions. Curing involves spreading the potatoes in a single layer in a dark, well-ventilated space with high humidity for about two weeks, ideally between 50°F and 60°F. After curing, store the potatoes long-term in a cool, dark, and moderately humid environment, such as a root cellar or unheated basement, maintained between 40°F and 46°F. Storing them in darkness prevents solanine formation, and the low temperature slows sprouting and shriveling, allowing the harvest to last for several months.