Biointensive Spacing for Asparagus

The Biointensive Method

• Biointensive gardening is a unified system of horticulture, so you cannot extract one aspect of the system and expect to achieve optimal results. The various parts of this highly detailed system are dependent on one another for success. This means that you may experience unsatisfactory growth or yield if you simply plant asparagus at the recommended biointensive spacing without following the biointensive approach to such cultural practices as soil preparation, irrigation, fertilization or composting.

The Basics of Biointensive

• The three pillars of the biointensive method are deep soil preparation, densely planted beds and carefully made compost as the primary source of nutrients and organic matter. Some less-critical aspects of the system are companion planting, growing crops as transplants whenever possible and seed saving. Irrigation is also an important consideration in biointensive gardens -- close plant spacings rapidly deplete available soil moisture, so regular irrigation is essential unless your soil can hold large quantities of water and you live in a region with frequent heavy rains during the growing season.

Asparagus in the Growing Bed

• Asparagus (Asparagus officianalis) is a long-lived perennial that is adapted to U.S. Department of Agriculture hardiness zones 2 to 8. It is grown for short, tender shoots or "spears" that are ready to harvest in spring when most other crops are a long way from maturity. Many gardeners start an asparagus bed by purchasing one-year-old crowns; this provides an earlier harvest and avoids the troublesome labor of tending slow-growing seedlings. The biointensive spacing for asparagus crowns planted directly in a growing bed is 12 inches. As with all biointensive spacings, this refers to a hexagonal planting pattern -- in other words, adjacent rows of plants are offset by half this distance, resulting in plants that are equally spaced in all directions.

Asparagus from Seed

• Despite the popularity of starting with purchased crowns, asparagus grows well when planted from seed. You can start the seeds about two months before the last spring frost, but your harvest will be delayed by one or two years relative to a crown planting. If you are able to house and tend asparagus seedlings through the winter, you can start them six months before the last spring frost and perhaps eliminate this lost time. According to biointensive guidelines, asparagus seeds should be started in a 3-inch-deep flat at a hexagonal spacing of 1 inch, and when the seedlings become crowded, they should be moved to a 6-inch-deep flat at a hexagonal spacing of 2 inches.