Asparagus is one of the only perennial vegetables; it will grow back each year for up to 20 years. Many consider asparagus a gourmet vegetable and think it is difficult to grow; however it's not that difficult providing you feed the plants well and keep the weeds from competing for water and nutrition. There are many varieties of asparagus, including the all male hybrid varieties that don't seed like the female plants, making the care of the garden much less time consuming. Grow asparagus in USDA planting zones 3 through 10. Choose 1-year-old asparagus crowns for planting.
Prepare the planting bed in late winter or early spring. Do this by placing ½ pound of 10-20-10 fertilizer per 100 sq. feet of bed and 2 to 3 inches of compost and till it in to a depth of 10 inches.
Test the soil PH. If the PH is less than 6.0 add 2 to 6 pounds of lime per 100 square feet and till again. The lower the PH number, the more lime will be needed. Let the soil sit for a week and test again to make sure the PH has risen.
Dig trenches with a hoe into the bed once the soil temperature has reached about 50 degrees. The trenches should be 10 inches deep and 10 inches wide, with rows at least 3 feet apart.
Mix compost and well-rotted manure to a ratio of 1 to 1 and cover the bottom of each trench 2 inches deep. Add one teaspoon of 0-46-0 fertilizer per each foot of row to the bottom of each trench. Cover the fertilizer with 1 inch of soil. Slightly mound soil in the bottom of each trench to prepare for the asparagus crowns.
Place the asparagus crowns on the mounds in the trenches spreading the roots. The crowns should be spaced 15 inches apart and covered immediately with 2 inches of soil. Stagger crowns from one row to the next to give the plants plenty of room to grow. Do not tamp the soil down.
Water well to completely soak the crowns and surrounding soil. Keep the soil evenly moist but not wet for the next 2 weeks while the roots are establishing. Water when the soil starts to dry from then on. Plants should break through in 3 to 4 weeks.
Fill in around the plants with more soil as they grow. Do not cover the foliage---just fill in around the bottom of the plant. Within four weeks the trenches should be level with the surrounding soil.