Asparagus

1. Establishing a Planting: Asparagus is typically planted by purchasing 1-year-old “crowns” or roots from a garden dealer, seed supplier or nurseryman. It is possible to start asparagus from seed, but takes an additional year to produce a crown ready to be transplanted. Gardeners wishing to try starting asparagus from seed may follow these recommendations:
   1. Choose an area of the garden as a nursery bed. Young asparagus plants will grow here for their first year. The site for the asparagus nursery should be level and have sandy soil.
   2. Plant seed in spring, about one inch deep, spaced two to three inches apart, within rows a foot apart. Seeds can take three weeks to germinate.
   3. Keep the nursery bed free from weeds, as the asparagus seedlings cannot compete with strong weed growth.
   4. Mulch the nursery bed with four to six inches of straw in late October to keep it warm during winter.
   5. In mid-March, before the plants start to grow, dig up the crowns with as much of the root system as you can, and move them to their permanent location, following the method described below for planting crowns.
   6. Asparagus crowns should be planted between March 15 and April 15 in Kansas with crowns set deeply in the soil. Start by digging a trench 8 to 9 inches deep. Place the crowns about 18 to 24 inches apart in the bottom of the trench. Rows should be 4 to 5 feet apart if planting more than one, but one row usually suffices. Cover the crowns with 2 to 3 inches of soil initially, firming the soil well around the crowns. Do not fill in the entire trench at once, but add soil gradually, filling in the trench as the plant grows. Small weeds that are covered in the process will die for a lack of light. The trench should be completely filled in by the end of the first season. Information on harvesting will be discussed under the Harvest section.
2. Sunlight: Asparagus thrives in full sun and performs best in locations receiving 8 or more hours of sunlight a day.
3. Watering: Asparagus tolerates a wide range of soil moisture levels. Soak the area during periods of drought but usually watering is not needed.
4. Soil and Fertilization: Asparagus prefers well draining soil with high levels of organic material. Before planting a new planting work organic material into the soils. Add barnyard manure, rotted sawdust, or compost to a depth of 2 inches over the area to be planted and work it into the soil by tilling or using a garden fork. New Plantings: Fertilizer should be applied to the soil in the spring before planting to establish a new planting. Have soil tested the fall before planting and add fertilizer according to recommendations. If a soil test was not done, add a “starter” fertilizer to the soil at the rate recommended on the label. A starter fertilizer for lawns can be used as long as it does not contain a weed preventer or weed killer. If organic matter was applied generously in the fall, use only half as much fertilizer as indicated by the soil test or the fertilizer label. Established plantings: Fertilize once a year after harvest using a fertilizer and rate recommended by a soil test or a complete, balanced fertilizer (10-10-10, 12-12-12 or something similar) at the rate suggested on the bag.
5. Pests and Diseases: Asparagus rust. On asparagus, rust appears as small reddish-brown spots on stems. It can spread causing the leaves of young shoots to die and fall off. New rust resistant strains of asparagus are available. Rust can be controlled in other varieties by applying a myclobutanil fungicide spray after the harvest season. Myclobutanil products include Immunox Multi-Purpose Fungicide for Gardens and F-Stop Lawn and Garden Fungicide. Asparagus beetle. Beetles ( inch long) have a red thorax and blue wing covers with yellow spots. Larvae and adults eat asparagus stems and leaves. Dark eggs are conspicuous when laid on stems. The asparagus beetle has 2 to 4 generations per year. Permethrin products are labeled for use against beetles, but require a three-day waiting period between spraying and harvest.
6. Weed Control- It is important to control weeds in the planting. There are several ways to control weeds including cultivation, hand pulling, and chemical control. Removing weeds by hand is still one of the most effective methods, especially in smaller asparagus beds. There are two times when asparagus beds can be cultivated: Before the spears come up in the spring, and after all of the spears are harvested but before ferns come up in June. If using a hoe, cultivator, or rotary tiller, till no deeper than 2 to 3 inches to avoid root damage. Chemical weed control options for home gardeners include trifluralin, which should be applied to weed-free soil before and after the cutting season on established beds. Apply at least ¼ inch of water immediately to activate the product.

The vigor of an asparagus planting depends on the food reserves transported to the roots during the previous season, so asparagus should not be harvested the first year from crowns. The next season, harvest for only 3 to 4 weeks, or until spear size rapidly decreases in diameter. Regular harvest can begin the third season and continue for 6 to 8 weeks in the spring. Newer hybrid varieties will be more productive the first and second cutting years. Most gardeners harvest young, tender spears 5 to 10 inches long. In El Dorado, Kansas, gardens, asparagus normally can be harvested by mid-April. Spear growth depends on the temperature. If it is warm, asparagus may need to be harvested every three days, and if hot, it may need to be harvested every day. Harvest while the tips of the spears are still tight. Spears that become too large should be cut and discarded, which allows new spears to emerge. Cut the spears or shoots with a sharp knife 1 to 2 inches below the soil surface, or cut or snap them off at the soil surface. Be careful to cut only the spear you want and not to damage other young spears just beneath the soil surface.

Trim and wash spears before eating. Asparagus can be prepared fresh, or it can be canned or frozen. A well tended planting should yield 80 to 100 pounds of fresh asparagus each year from 1,000 square feet of bed space. Fresh asparagus will keep 1-2 weeks in the refrigerator. Refrigerate upright with cut ends in water or with cut ends wrapped in wet paper towels in a plastic bag. Trim just the pale ends of the stalks, where the color turns from white to green, to remove the tough, woody part. One pound of asparagus will yield 4 one-half cup servings, about 6 spears per serving.

Asparagus is typically cooked (steamed, grilled, or roasted) but the tender green tops can be eaten raw if eaten when they are young. Here are some tasty recipes for using asparagus.

Roasted Asparagus with Balsamic Glaze

Recipe source: North Dakota State University Extension

Asparagus and Orange Salad

Recipe source: University of Missouri Extension

Pasta Primavera

Recipe source: University of Missouri Extension