The potato is one of the world’s most significant food crops. Modern commercial production operates on a massive scale, requiring advanced planning and technology to maximize yield and quality for global markets. This large-scale farming involves specialized equipment and precise management from field selection until the final product is stored.
Preparing the Field and Selecting Varieties
The commercial growing cycle begins with field preparation and variety selection, which affects the final crop quality. Potatoes thrive in loose, well-drained, sandy loam soils that allow for easy tuber expansion and harvest. Growers aim for a slightly acidic soil pH, typically between 5.5 and 6.5, because alkalinity increases the risk of common scab.
Maintaining soil health and controlling disease necessitates strict crop rotation, often requiring fields to be potato-free for a minimum of two years. Variety selection is determined by the intended market, as different cultivars possess unique characteristics. For instance, the Russet Burbank is preferred for processing into french fries due to its high dry matter content, while varieties like Yukon Gold are favored for the fresh market.
Planting Methods and Mid-Season Care
Commercial planting utilizes certified seed potatoes, which are tubers cut into “seed pieces” containing at least one eye or sprout. Specialized mechanical planters ensure precise spacing and depth, placing the seed pieces into the prepared rows. The soil temperature must be at least 45°F for planting to ensure successful germination and emergence.
A defining practice is hilling, which involves mechanically mounding soil around the growing stems. Tubers grow from underground stems called stolons, and hilling provides the necessary loose soil volume for them to expand. Hilling also protects the developing tubers from sunlight exposure, which prevents them from turning green.
Water management often relies on large-scale systems like center pivot irrigation to deliver water uniformly. Potatoes are highly sensitive to water stress; insufficient moisture reduces tuber size, while excessive water promotes diseases like late blight. Throughout the season, an Integrated Pest Management (IPM) strategy is employed, combining scouting and targeted chemical applications to control threats like the Colorado potato beetle.
Commercial Harvesting Procedures
The harvesting phase begins with vine killing, or desiccation, which is the intentional destruction of the plant’s foliage. This is done two to three weeks before harvest using chemical sprays or mechanical flail choppers. Vine killing stops tuber growth, achieves a uniform size, and allows the potato skin to mature and “set,” which reduces bruising and improves storage life.
The crop is removed by large, specialized potato harvesters, which lift the row and separate the tubers from the soil and vines using conveyor chains. The objective is to minimize mechanical damage. Potatoes are harvested when tuber temperatures are between 45°F and 60°F to further reduce the risk of impact bruising. The tubers are immediately transferred into padded trucks for transport to a storage or packing facility.
Curing and Long-Term Storage
Potatoes destined for long-term storage first undergo curing. Curing is a period of high humidity and moderate temperature, typically lasting seven to fourteen days. These conditions encourage suberization, a natural wound-healing process that forms a protective layer beneath any cuts or bruises incurred during harvest, which is essential for resisting decay.
After curing, the temperature is gradually lowered to the final long-term holding temperature, determined by the potato’s end-use. Fresh market or seed potatoes are stored at cooler temperatures (38°F to 45°F), while processing potatoes are kept warmer (45°F to 55°F) to prevent starches from converting to sugars. Maintaining a dark, cool, and high-humidity environment is necessary to minimize weight loss, prevent sprouting, and ensure a year-round supply.