The Best Time to Plant Seed Potatoes
Solanum tuberosum, the common potato, grows in U.S. Department of Agriculture hardiness zones 1 through 7. The versatility of the vegetable and the ease of planting and growing make the potato a good choice for any garden. The key to successful potato growing is soil preparation, plant care and choosing the best time to plant seed potatoes.
Seed Potato Treatment
Certified seed potatoes are whole potatoes that contain several "eyes." The eyes are areas of the potato that send out shoots to form roots. Cut the seed potatoes into sections that are about the size of a golf ball. Before making the cuts, make sure each section has two or three eyes so it will produce. Allow the sections to air-dry for about three days so the cut sides form a callus. The best time to plant the sections is after the calluses form so the seed potato sections do not rot from bacteria in the soil.
The best time to plant the callused potato sections is after the soil has been tilled to loosen the compacted earth. The tubers need room to form and grow without obstructions. As you till the soil, remove any large rocks or other debris that could stunt the growth of the potatoes. Till the soil to a depth of about 12 inches when growing potatoes in hills or rows. Plant the seed potato sections about 3 inches deep. The depth allows the potatoes to form without breaking the surface and causing green spots on the potatoes. When a tuber is exposed to light for an extended period of time, a poisonous alkaloid is produced that turns the potato green.
Fertilizer and Manure
Potatoes need nitrogen to grow and produce a healthy crop. Before planting, add a fertilizer with a 10-10-5 formula listed on the package. Mix the fertilizer in with the soil as you till to evenly disperse the additives. If you use an organic fertilizer, such as cow or horse manure, make sure the manure is well-rotted or at least a year old. Fresh manure causes the planting bed to get too "hot" and burns the plants. Manure that has had a year to break down and ferment is best for the garden. Plant seed potatoes after you have added the fertilizer or manure to the soil.
Some vegetables, like tomatoes, prefer a warm soil to set roots and grow. Potato seeds prefer a cooler temperature to set roots. The ideal soil temperature for planting seed potatoes is around 55 degrees Fahrenheit. Colder temperatures keep the seed potatoes from growing the roots and results in a rotted potato section. A cool temperature allows the potato to grow roots and form a strong vine that collects the energy used to form the tubers. The more nourishment collected, the bigger the potato harvest, because potatoes are the stored energy of the potato plant.
- Digital Vision./Digital Vision/Getty Images