Blackwelder column: Asparagus requires a little patience to get best results

Published 12:00 am Friday, March 23, 2012

SALISBURY — Although asparagus is considered a northern vegetable, any home gardener in Rowan County can grow and enjoy this vegetable. In many realms, the vegetative stem is considered the queen of vegetables.
Mary Washington is a standard variety for most home gardeners. However, male hybrids Jersey Gem and Greenwich are more productive and somewhat tolerant to leaf diseases. Plants are sold as 1-year-old crowns at local garden centers and retail outlets.
Properly managed, this perennial vegetable will produce spears for 15 years or more. Site selection is critical since this is a perennial vegetable. Place asparagus in a permanent location, away from other vegetables, that receives full sun, has well drained soil, preferably a sandy loam. If the soil is predominantly clay, condition it with well rotted leaf mold or compost and Permatil.
Since asparagus is a perennial crop, it’s best to have the soil tested and amended before planting. Asparagus grows best in slightly acidic soils with a pH of 6.0-6.7. The site should also be free of nutsedge or Bermuda grass.
Green manure, animal manure, straw or leaf mold can be used as another way to increase organic matter. It is best to start bed preparation a year in advance if the soil is extremely poor.
Crowns have similar appearance to hosta crowns and should be planted in rows 5 feet apart with the crowns spaced 12 inches apart in the rows. Use 3 to 5 pounds of 5-10-10 and 10 pounds of lime per 100 square foot bed in addition to organic matter to enrich the soil. Shorter distances between the rows shortens the life of the bed.
Place the crowns 6-8 inches deep in the bottom of the furrow. Make sure that the buds are facing upwards. Cover with 2-3 inches of soil. After growth begins, rake about an inch of soil a week over the sprouts until the furrow is filled. The bed should then be mulched with leaves, well-rotted sawdust or clippings to discourage weed growth.
It is important not to harvest asparagus the first growing season after planting the crowns. Harvesting should begin two weeks into the second growing season. Harvesting too early often results in weak, small spears. After the third year, the crop can be harvested for six-eight weeks. Spears can be cut or snapped when they reach a height of 8 inches at or below the soil line, taking care not to damage emerging spears.
Darrell Blackwelder is the County Extension Director with horticulture responsibilities with the North Carolina Cooperative Extension Service in Rowan County. Questions can be emailed to Learn more about Cooperative Extension events and activities by calling 704-216-8970 Facebook or online at