Seed Potatoes Grades and Standards

Grades of Seed Potatoes

  1. U.S. No. 1 Seed Potatoes consist of unwashed potatoes identified as certified seed by the state of origin by blue tags fixed to the containers or official State or Federal State certificates accompanying bulk loads, which identify the variety, size, class, crop year, and grower or shipper of the potatoes, and the State certification agency. These potatoes must meet the following requirements:
a. Fairly well shaped.
b. Free from:
1. Freezing injury;
2. Blackheart;
3. Late Blight Tuber Rot;
4. Nematode or Tuber Moth injury;
5. Bacterial Ring Rot;
6. Soft rot or wet breakdown; and,
7. Fresh cuts or fresh broken-off second growth.
c. Free from serious damage caused by:
1. Hollow Heart; and,
2. Vascular ring discoloration.
d. Free from damage by soil and any other cause. (See §51.3005 - 06).
e. Size:
1. Minimum diameter, unless otherwise specified, shall not be less than 1-1/2 inches (38.1 mm) in diameter;
2. Maximum size, unless otherwise specified, shall not exceed 3-1/4 inches (82.6 mm) in diameter or 12 ounces (340.20 g) in weight.
f. Tolerances. (See §51.3002).

Detailed standards, Inspection Instructions & Other Resources: