5 Asparagus Crown, Jersey Knight 2 Year Roots,Large, green spears tipped ! 5 Asparagus Crown, Jersey Knight 2 Year Roots,Large, green spears tipped ! Jersey Knight is an all-male variety of asparagus that offers cold hardiness and resistance to diseases such as root rot, rust and fusarium. Like other varieties of asparagus, Jersey Knight is high in fiber, potassium and folic acid, as well as vitamins A, B6 and C. Jersey Knight is hardy in U.S. Department of Agriculture zones 3 through 10. Gardeners often grow asparagus from year-old crowns to speed crop production. Amend your soil the fall before planting asparagus crowns to boost potassium and phosphorus. Apply 20 pounds of 10-20-10 fertilizer or mature compost per 1,000 square feet of soil. Work the fertilizer into the soil at a depth of 6 inches. 2 Select a planting site. Asparagus needs well-drained soil and full sunlight. The crowns thrive in sandy loam soil, but they will grow in other soil types. Dig a trench for asparagus crowns in early spring, after the last frost date has passed for your area. Make trenches 5 inches deep and 6 to 8 inches apart. Planting deeper than 5 inches may result in reduced yields. 4 Add 2 pounds of 0-20-0 superphosphate or 1 pound of 0-46-0 triple superphosphate to the bottom of each 50-foot row. Cover the fertilizer with a 1-inch layer of soil. Soak the asparagus crowns in lukewarm water for several minutes before planting. 6 Place asparagus crowns about 18 inches apart in the trenches with the buds pointing up. Gently loosen the roots and allow them to drape over the sides of the trenches.