Asparagus is a perennial plant that produces edible sprouts every spring for 20 years are longer. It is considered a permanent part of the garden, so plant asparagus in a location that get lots of sun and where the tall ferns cannot shade out other plants. When purchasing asparagus roots, or crowns, to plant, buy year-old crowns of a male variety such as Jersey Giant or Jersey Knight for best sprout production. Asparagus spears, or sprouts, should not be harvested the first spring after they are planted to give the plants time to get established.
Locate a well-drained place in the garden that receives at least six hours of full sun each day for your asparagus planting area. Asparagus ferns grow up to 6 feet tall during the summer, so the plants must be given plenty of room. Crowns are planted 12 inches apart, so plan accordingly.
Clear the area of all weeds and garden debris. Pulverize the soil to a depth of at least 8 inches, then spread a 1- to 2-inch layer of well-rotted compost over the planting area. Use a hoe to work the compost into the soil to a depth of 6 inches and rake the area smooth.
Dig a trench 6 inches deep for planting the crowns. The soil should be rich with compost. Spread 1 lb. of 0-46-0 fertilizer, which is rich in phosphorus, an important element for root development, per 50 feet of row in the planting trench. It is OK if the crowns have direct contact with the fertilizer because it does not contain nitrogen.
Place the crowns in the trench 12 inches apart. Gently push them into the fertilizer, compost and soil mixture so the bottom middle of the crown has contact with planting medium. The correct position of the crown is when the legs, or roots, are dangling downward and the crown resembles a spider.
Fill the trench with soil and compost mixture. Do not pack down the soil, just gently set the loose, pulverized soil into the trench using your hands, shovel or hoe. Sprinkle the planting area gently with water. Keep moist, but not wet, as the first sprouts appear and during the first year of growth until established.