Canning Spinach and other Greens Quantity: An average of 28 pounds is needed per canner load of 7 quarts; an average of 18 pounds is needed per canner load of 9 pints. A bushel weighs 18 pounds and yields 3 to 9 quarts--an average of 4 pounds per quart. Quality: Can only freshly harvested greens. Discard any wilted, discolored, diseased, or insect-damaged leaves. Leaves should be tender and attractive in color. Procedure: Wash only small amounts of greens at one time. Drain water and continue rinsing until water is clear and free of grit. Cut out tough stems and midribs. Place 1 pound of greens at a time in cheesecloth bag or blancher basket and steam 3 to 5 minutes or until well wilted. Add 1/2 teaspoon of salt to each quart jar, if desired. Fill jars loosely with greens and add fresh boiling water, leaving 1-inch headspace. Adjust lids and process following the recommendations in Table 1 and Table 2. Table 1. Recommended process time for Spinach and Other Greens in a dial-gauge pressure canner. Canner Pressure (PSI) at Altitudes of Style of Pack Jar Size Process Time 0 - 2,000 ft 2,001 - 4,000 ft 4,001 - 6,000 ft 6,001 - 8,000 ft Hot Pints Quarts 70 min 90 11 lb 11 12 lb 12 13 lb 13 14 lb 14 Table 2. Recommended process time for Spinach and Other Greens in a weighted-gauge pressure canner. Canner Pressure (PSI) at Altitudes of Style of Pack Jar Size Process Time 0 - 1,000 ft Above 1,000 ft Hot Pints Quarts 70 min 90 10 lb 10 15 lb 15