Asparagus is a perennial plant that is actually a member of the lily family. This long-lived vegetable is a favorite among both experienced and novice gardeners, producing for 15 years or more if grown in the right conditions and properly cared for. Harvest is done in the late spring through early summer for about six to seven weeks consecutively, and any unharvested spears grow into ferns with red berries that store up nutrients and minerals for next season's crop. Asparagus is a nutrient-dense food, high in folic acid and a good source of potassium and B6, A and C vitamins.
Plant asparagus in early spring as soon as the ground is workable, usually after the last frost. Prepare the beds by digging trenches that are about 18 inches deep and wide with 1 foot between trenches.
Add 6 inches of organic soil, compost or manure into each trench. Mound up the soil, compost or manure in the bottom of the trenches.
Place the asparagus crowns into the trenches, spreading out the roots of each crown over the mounds. Space each crown 18 inches apart with crowns about 6 inches below the ground surface.
Cover the crowns with 1 inch of organic soil. As the shoots emerge from each crown, cover with another 1 inch layer of soil. Continue covering new shoots with soil until the trench is completely filled to the top surface with soil.
Water the trenches deeply each week using a drip irrigation or garden hose with the water trickling out slowly. Keep the soil moist, but never let it get soggy.
Cut ferns that grow in the first year of planting back to the ground and cover with manure. The following spring, harvest only a few shoots that appear, and in the fall, cut the ferns back and cover with manure.
Harvest in the third year from mid-April in early summer for six to seven weeks when the spears are 5 to7 inches tall. Cut the asparagus spears off 2 to 3 inches below the ground with a sharp knife. Each fall, cut back the ferns and cover with manure.