How to Grow Asparagus

Set out asparagus crowns in spring when all danger of frost has passed. Start seed indoors 12 to 14 weeks before the last frost. Asparagus requires 3 years to become established and full productive.

Description. Asparagus is a hardy perennial that produces tender, fleshy, green stems or “spears” with bud-forming caps. Grown to maturity the asparagus has fernlike, feathery foliage. The asparagus is long-lived staying in the garden for 15 years or longer.

Yield. Plant between 30 and 40 plants to feed 2 to 4 people several meals.

Site. Plant asparagus in full sun; asparagus will tolerate partial shade. Asparagus needs well-drained soil with a pH over 6.0. Set out asparagus crowns in spring when all danger of frost has passed. Start seed indoors 12 to 14 weeks before the last frost. Asparagus requires 3 years to become established and fully productive.

Planting and spacing. Loosen the soil from 8 to 10 inches deep adding well-aged compost. Asparagus is most commonly grown from crowns; choose one-year-old crowns that are well-rooted and have not gone dry. Dig a trench or furrow 10 inches wide and 10 to 12 inches deep, and place a 2 to 4 inches tall mound of loose soil in the bottom of the trench. Space crowns in the prepared trenches 18 inches to 28 inches apart. Spread the crowns out at the bottom of the trench and cover with 2 more inches of soil. As the spears grow in spring, gradually fill in the trench to the top.

Starting asparagus from seed. Sow seeds in flats 1½ inches deep. Grow seedlings on until they are 1 year old.

Water and feeding. Keep asparagus moist but not wet when the spears are forming. Plants will survive without extra watering, but the stalks may become stringy and woody. Add a high phosphorus and potasium fertilizer, such as 5-10-10, before spears appear in spring and again at the end of harvest.

Companion plants. Tomatoes, parsley, and basil. Avoid planting asparagus near root vegetables

Care. Keep asparagus beds well weeded. Competition from weeds will lower the yield. Cut plants back to 1 inch in autumn and mulch with organic matter in cold-winter regions.

Container growing. Asparagus is a perennial that needs a cold period for dormancy. It may be difficult to provide these conditions in a container.

Pests. Asparagus beetles may attack asparagus in commercial asparagus growing districts. Pick off and destroy asparagus beetles.

Diseases. Asparagus is generally disease free. Asparagus rust may develop. Do not handle plants when they are wet. Choose rust-resistant varieties to lessen the incidence of the disease Do not handle plants when they are wet..

Harvest. Begin the asparagus harvest when plants are three years old and fully developed. During the third season, cut spears slightly below soil level being careful not to damage spears that have not yet emerged. Cut spears when they are 8 to 10 inches tall and at least the diameter of a pencil, not less. When buds begin to feather out, it is too late to eat them. Harvest third year spears for 2 weeks and fourth year plants for 4 or more weeks.

Storing and preserving. Asparagus will keep for up to 1 week in the refrigerator. Place spear upright in an inch or so of water. Freeze asparagus after blanching. Asparagus is best eaten fresh.

Varieties. Jersey Knight, Larac, Mary Washington, UC 157, Viking, Waltham.

Common name. Asparagus

Botanical name. Asparagus officinalis

Origin. Mediterranean

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