Growing Asparagus
GROWING ASPARAGUS
THE PLANTING SITE
Choose a permanent location in full sun. Ideally, the area should be well drained with loose, worked-up soil. The planting spot should be free of grass and weeds. If needful, add lime to raise the soil to 7.0-7.2 pH. Adding bone meal or a source of phosphorus can also be beneficial. A small amount of fertilizer such as 10-10-10 or a similar organic source can be worked into the soil prior to planting. An amount of 3-5 pounds per 100 sq. ft. is generally ideal.
SPACING
Space each crown 12”-14” apart. Allow approximately 3’ between the rows. If you plan on keeping the rows cultivated, the spacing is subject to the method of cultivation.
PLANTING
The root crowns should be placed in a trench or planting furrow that is 8”-10” deep. (See diagram below) The crowns should be pointed upward and the roots spread outward. Cover them lightly with several inches of topsoil or a topsoil compost mix. Allow the crowns to start pushing growth. Then continue to fill the trench as the plant spears begin to grow through the soil. A good topsoil of compost/soil mix can be added continually into the trench. Fill the trench as the plant spears grow up to surrounding soil level.
FERTILIZING
A starter fertilizer can be incorporated into the soil prior to planting. Use an organic all-purpose low nitrogen compost fertilizer or a 10-10-10 garden fertilizer. Work well into the soil. Use 3-5 pounds per 100 sq. ft. In late summer (Aug-Sept) when the plants are well established, an additional fertilizer can be applied along each row. Add about 2 pounds to each 100 ft. of row. Side dress with lime as needed to maintain a soil pH lever of 7.0-7.2.
IRRIGATION
Maintain adequate moisture during the first year of establishment. Irrigate as needed. Light sandy soils may require at least twice a week watering during the first summer.
MULCHING AND WEED CONTROL
Apply a light cover of straw, hay, or compost mulch over the row area to prevent drying out and assist in controlling weed pressure.
CARING FOR YOUR ASPARAGUS PLANTING
Asparagus is an attractive, fern-like perennial vegetable. The young shoots are rich in vitamin B, C, calcium and iron. It is one of the first spring vegetables you can harvest. It has relatively few pests.
HARVESTING
Do not harvest any spears the same year of planting. Some light harvesting can be done the second year, especially in some vigorous stands. Each year the harvest can be extended. Full production should be reached by year four to six. By year four the harvest may continue for up to eight weeks. Discontinue cutting when stalks are less than 3/8-1/2 inch in diameter. In early spring, harvest every three days. As the weather warms up you may have to cut every day to keep harvesting uniform size spears. A well-maintained bed can produce for many years.
MAINTAINING THE BED
Shoots that are not harvested will develop into a large fern plant. The fern part can be left standing all winter or be mowed off or cut down in the fall. If left standing over winter, it should be cut down in the spring before the new shoots emerge. In commercial plantings, a pre-emergent herbicide can be applied at this time.
FERTILIZATION
Broadcast a balanced N-P-K fertilizer, natural plant food, or light compost over the bed in springtime just before spears emerge. Asparagus responds to a good fertilizing and irrigation program. Use 5-10 pounds for each 100 sq. ft. Maintain a soil pH of 7.0-7.2.
WEED CONTROL
If no herbicide is used, apply old hay mulch or compost, to help smother weeds that compete with the emerging spears. Salt (sodium chloride/rock salt) can be applied to beds more than a year old. Generally salt is not recommended as a soil amendment. However, asparagus is tolerant to salt. Never apply more than 2 1/2 pounds per 100’ row. Some tests have shown this treatment in late winter, early spring, can help resist Fusarium fungi. It is important NOT to use iodized table salt or any salt derived from calcium chloride!
Courtesy of Schlabach's Nursery. For more information, we recommend David Schlabach's book, Backyard Fruit Production, which we have available for purchase.