The Yukon Gold potato, prized for its buttery flavor and signature yellow flesh, is a popular mid-season variety. Gardeners typically harvest these tubers between 70 and 90 days after planting the seed potatoes. This relatively short growing period places the Yukon Gold in the “mid-early” category, making it an excellent choice for regions with shorter growing seasons. The final harvest time depends on whether the goal is to pick small, tender “new potatoes” or large, mature tubers suitable for long-term storage.
Preparation and Planting Timing
The successful growth timeline for Yukon Gold potatoes begins with proper preparation of the seed potato. This involves “chitting,” or pre-sprouting, where seed pieces are placed in a light, cool area (around 50°F to 60°F) for several weeks. This exposure encourages the formation of short, stubby sprouts, giving the plant a head start once it is placed in the ground.
Planting should occur in early spring, once the danger of a hard frost has passed and the soil temperature has warmed to at least 40°F. A temperature of 50°F is considered optimal for strong growth and to prevent rot. A common guideline is to plant two to three weeks before the average last frost date. The seed pieces, each containing at least one “eye,” are placed about four inches deep in well-drained, loose soil rich in organic matter.
The soil’s composition is important, as potatoes thrive in a slightly acidic environment with a pH between 5.8 and 6.5. This helps prevent common issues like potato scab, which affects the tuber’s appearance. Proper soil preparation and timely planting ensure the potato plant quickly enters its vegetative growth phase.
Monitoring the Growth Timeline
The initial stage, known as sprout development, typically sees shoots emerging from the soil two to six weeks after planting. This is followed by rapid vegetative growth, where the plant produces a dense canopy of leaves and stems above ground. New tubers begin to form on underground stems called stolons, usually five to six weeks after the sprouts first appear.
Around 70 to 80 days after planting, the plant may begin to flower, signaling that the first wave of tubers is beginning the bulking stage. This marks the earliest time to carefully harvest small, thin-skinned “new potatoes” from the edges of the plant without disturbing the main crop. Consistent moisture is important during this phase, as water fluctuations can lead to misshapen or cracked tubers.
A crucial maintenance task is “hilling,” which involves mounding soil up around the growing stems as they reach eight to ten inches in height. Hilling serves a dual purpose: it encourages more tubers to form along the buried stem. It also protects developing potatoes from sunlight exposure, which causes them to turn green and produce solanine. This process is repeated several times as the plant grows to ensure all tubers remain covered.
Recognizing and Harvesting Mature Potatoes
The signal that the main crop is reaching maturity is the natural dying back of the plant’s foliage, or vines. The leaves will begin to yellow, wilt, and eventually turn brown and collapse, indicating the plant has finished its energy-producing cycle above ground. This process typically occurs around the 90-day mark, though it can be as early as 75 days depending on growing conditions.
Once the foliage has died back completely, leave the mature potatoes in the ground for an additional two weeks before harvesting. This waiting period allows the skin of the tubers to “set” or toughen, which reduces damage and bruising during harvest and improves storage life. Harvesting should be done gently with a pitchfork or shovel, digging several inches away from the main plant stem to avoid piercing the potatoes.
Immediately after harvest, the potatoes need to undergo a “curing” process to heal minor nicks and further thicken the skin. Curing involves spreading the unwashed tubers in a single layer in a cool (45°F to 60°F), dark, and humid area for one to two weeks. Once cured, the potatoes should be stored in a dark, cool location, ideally around 40°F, with good ventilation to maximize longevity.