By William Terry Kelley
University of Georgia
Both male and female plants produce spears. The female produces larger spears, but male plants are preferred, since they produce higher yields and have greater longevity. Along the spears are triangular bracts, which are the true leaves.
Modified stems, called cladophylls, make up the highly visible fern growth. The fruit is a red berry with one to five seeds. Birds feed on the seed pods and can distribute the seeds.
Cool veggieAsparagus is considered a cool-season plant but grows in many environments. Average day-night temperatures of 70-50 are ideal, but it's climatically well suited to most of Georgia.
Since asparagus plantings have a long life, site selection is critical. Choose a spot out of the way of normal garden jobs and in full sunlight, where the soil is loose and well-drained. East or north ends of the garden are best so as not to shade low growing crops.
Any soil type will work for asparagus. But it won't tolerate wet soil, and it needs 8 to 10 inches of topsoil. If you don't have such a spot, you may grow asparagus in raised beds where you provide the required soil and nutrients.
Add organic matter and lime (to a pH of 6.2 to 6.8) several months before you plant. Animal manure or decomposed organic matter, such as leaves or old sawdust, can be used. Add 3 to 4 pounds of 34-0-0 per 100 row feet, too, to feed the bacteria that break down organic matter.
Getting startedSeveral varieties produce well. Newer varieties such as Jersey King, Jersey Knight and Jersey General have resistance to asparagus rust and are adapted to warmer climates. Asparagus can be started from seed or crowns. One-year-old crowns are best.
Fertilize according to soil test recommendations for phosphorous and potassium. In general, broadcast and incorporate 1 to 2 pounds of 10-10-10 fertilizer (or the equivalent) per 100 square feet and mix well with the soil.
Then prepare a trench 12 inches deep and 12 to 18 inches wide. Fill the bottom 4 inches with organic material and cover with a layer of soil.
Space crowns 10 to 12 inches apart, in rows 4 to 5 feet apart. Lay crowns on their side at the bottom of the furrow 6 to 8 inches deep and cover with 1 to 3 inches of soil. Gradually fill in the trench with soil as the ferns grow, but don't cover the growing tip.
In raised beds, space crowns 24 inches apart in all directions and cover the same way. Add another 1 to 2 pounds of 10-10-10 in late summer or early fall. Water enough to soak the soil to crown depth.
How to harvestHarvest only two or three times in the spring one year after planting. You should be able to harvest for about two months in succeeding years.
Cut spears about an inch below the soil surface when they're 6 to 8 inches long and the heads are tight. After you stop cutting, allow the tops to develop and produce ferns.
Use shallow cultivation to remove weeds in successive seasons. Top-dress each year with 5-10-15 by broadcasting 4 to 5 pounds of fertilizer in late February to early March for each 100 square feet. Apply again just after harvest ends.
Cut the tops to ground level after they die back.
(Terry Kelley is an Extension horticulturist with the University of Georgia College of Agricultural and Environmental Sciences.)
(Terry Kelley is a former University of Georgia Cooperative Extension horticulturist with the UGA College of Agricultural and Environmental Sciences.)