March 17 -- St. Patrick's Day -- traditionally signals the date for planting potatoes in home gardens.
Time to plant potatoes in Kansas
K-State horticulture expert shares tips for successful crop
At a glance: St. Patrick’s Day is the traditional signal to plant potatoes in Kansas, said K-State horticultural expert Cynthia Domenghini.
More information: Cynthia Domenghini, Cdom@ksu.edu
Related: K-State Horticulture Newsletter
March 11, 2025
K-State Research and Extension news service
MANHATTAN, Kan. — For Kansas gardeners, St. Patrick’s Day means something much more than donning a favorite green outfit and heading to local celebrations.
Traditionally, the Irish holiday signals the date for planting potatoes.
“Actually, anytime from mid- to late-March is fine for potato planting,” said Kansas State University horticulture expert Cynthia Domenghini.
“Be sure to buy seed potatoes rather than using those intended for cooking. Seed potatoes are certified disease free and have plenty of starch to sprout as quickly as soil temperatures allow.”
Domenghini notes that most seed potatoes can be cut into four pieces – “though large potatoes may yield more,” she said. Each seed should weigh between 1 ½ to 2 ounces, and likely have more than one eye.
Each pound of seed potatoes should yield 8 to 10 pieces, according to Domenghini.
“Cut the seed 2 to 3 days before planting so that freshly cut surfaces have a chance to suberize, or toughen, which provides a protective coating,” Domenghini said. “Storing seed in a warm location during suberization will speed the process.”
Domenghini recommends planting each seed piece 1 to 2 inches deep and 8 to 12 inches apart in rows.
“Though it is important to plant potatoes in March, they emerge slowly,” she said. “It is often mid- to late-April before new plants poke their way through the soil. As the potatoes grow, pull soil up to the base of the plants. New potatoes are borne above the planted seed piece and it is important to keep sunlight from hitting the new potatoes.”
Domenghini said exposed potatoes will turn green and produce a poisonous substance called solanine. Keeping the potatoes covered will prevent this.
Domenghini and her colleagues in K-State’s Department of Horticulture and Natural Resources produce a weekly Horticulture Newsletter with tips for maintaining home landscapes and gardens.
Interested persons can subscribe to the newsletter, as well as send their garden and yard-related questions to hortsupport@ksu.edu, or contact your local K-State Research and Extension office.
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K‑State Research and Extension is a short name for the Kansas State University Agricultural Experiment Station and Cooperative Extension Service, a program designed to generate and distribute useful knowledge for the well‑being of Kansans. Supported by county, state, federal and private funds, the program has county extension offices, experiment fields, area extension offices and regional research centers statewide. Its headquarters is on the K‑State campus in Manhattan. For more information, visit www.ksre.ksu.edu. K-State Research and Extension is an equal opportunity provider and employer.