The easiest way to start asparagus is from crowns.
Plant crowns in the spring as soon as the soil can be worked.
Plants will take three growing seasons to become established.
Allow ten to twenty plants per person (15 to 30 feet of row).
Preparation
Select a well-drained site in at least part sun; full sun is not necessary.
Asparagus will thrive in slightly acid soil (pH of about 6.5), but will tolerate alkaline conditions up to 9.0.
Eliminate all weeds by repeated tilling or by growing a cover crop a year in advance.
About one week before planting, prepare trenches for crowns.
Planting
Soak the crowns briefly in lukewarm water before planting.
Draw a hoe along each side of the prepared trench to form a mound in the center running the length of the trench.
Set the crowns 18 inches apart on the mounds in the trench, draping the roots over the sides.
To cover the crowns, mix one part manure to 3 parts topsoil and bury the crowns 2 inches deep.
Water the bed thoroughly.
Care
First year: Weed the beds carefully. Periodically add more topsoil/manure around emerging shoots until the trench is filled. Then spread a 4-to 8-inch layer of mulch such as hay or leaves or a 3-to 4-inch layer of aged manure, compost, or shredded bark around the base of the asparagus ferns. Water regularly. In the early fall, pull back the mulch and side-dress with 2 1/2 pounds of a balanced fertilizer per 100 square feet. Cut down dead ferns in late fall and side-dress with 2 1/2 pounds phosphate fertilizer per 100 square feet.
Second year: Cultivate lightly by hand until the new spears are several inches tall. Keep the bed thickly mulched. Side-dress with a balanced fertilizer such as 10-10-10 at the rate of 2 1/2 pounds per 100 square feet in the spring and early fall. Follow first year instructions for late fall.
Third year and beyond: Maintain as for the second year, but apply the spring side-dressing after the harvest.
Harvesting
Plants started from crowns can be harvested lightly in the spring of the second year; plants started from seeds in the third year.
Harvest only those spears that are thicker than a pencil.
Cut off the spears at or just above ground level when they are 6 to 8 inches tall.