key growing information

Growing Asparagus From Crowns or Seed

How to grow asparagus from crowns or seed: site and soil preparation, starting seedlings, planting depth and spacing, establishment care, and a year-by-year harvest plan.

By Hensley’s Seed Co. September 3, 2026

Asparagus - Key Growing Information

SCIENTIFIC NAME:

Asparagus officinalis

CULTURE:

Asparagus is a perennial that, in a good site with careful preparation and care, can keep producing for 15 years or longer. Choose full sun or light shade and fertile, well-drained soil; extension guides recommend a pH close to neutral, roughly 6.5–7.5. Test the soil and prepare the bed the season before you plant. In warm Southern states such as TX, MS, GA, LA, AL and FL, plants often fail to go fully dormant, which leaves them open to frost and freeze injury, so results there may be poor.

GROWING FROM SEEDS:

Start seed indoors 12–14 weeks before your transplant date, one seed per 2" cell, ½–¾" deep. Germinate at 75–80°F (23–27°C) by day and 65°F (18°C) at night, and feed moderately as needed. After the last frost, plant seedlings much as you would crowns, but in a W-shaped furrow, setting them in the center of the W for better drainage. Fill the furrow in gradually as they grow, taking care not to cover the small ferns.

PLANTING CROWNS:

Set crowns out roughly 3–4 weeks before your average last frost. Open a furrow 5–8" deep (shallower on heavy soil, deeper in cold regions) and lay crowns in it buds up with roots fanned out. In the row, space green varieties 8–14" apart and purple varieties 6–8" apart; the tighter spacing gives purple types thinner spears. Leave 3–6' between rows. Cover with 2–3" of soil at first, then keep filling the furrow as spears emerge. Cultivate carefully so crowns are not injured. Control weeds (a straw or leaf mulch helps) and water regularly while plants establish. Leave the ferns standing until they die back in fall, and top-dress beds with compost or aged manure every fall or early spring.

HARVEST:

In the first spring after planting, harvest for only 7–10 days; in the second, for 2–3 weeks; from the third year on, for up to 6 weeks. Market-quality spears are about 6–9" long and at least as thick as a pencil. Snap spears off by bending them, or cut just below the soil line, and stop harvesting once new spears come up thinner than a pencil. Spears keep up to 2 weeks stored upright at 36°F (2°C) and 95–100% relative humidity.

SEEDS/LB. (AVG.):

16,000.

PACKET:

30 seeds per packet, enough for roughly 25' depending on spacing.