Asparagus is one of the most rewarding vegetables that can be grown in the home garden. Cooked soon after harvest, it has wonderful flavor, much better than when store-bought.It loses that superlative quality quickly.
There is a way to keep it fresh for several days after harvesting, according to Drs. Stephen A. Garrison and J. Howard Ellison, Rutgers University professors of vegetable crops. Wash the spears, place the cut ends in a shallow pan of water and refrigerate them immediately.
Good quality can be maintained for several days if the spears are kept at 35 to 40 degrees, they say.
Asparagus is one of the first spring vegetable crops, and with good care can yield for about eight weeks every year for up to 25 years. It is low in calories but high in flavor. A serving of four spears (60 grams) contains just 10 calories, one gram of protein, two grams of carbohydrates and only traces of fat.
No spears should be cut until the third season, and then only for about two weeks. During the fourth year the harvest can last four weeks, and for eight weeks each eyar thereafter. In the central valley of California, a 4-8-12 week sequence is best.
Cutting too soon after planting or extending the cutting season too late into summer limits the amount of food reserves that can be accumulated in the roots, reducing the following year's crop.
In the life of an asparagus planting, the sixth, seventh and eight harvest seasons usually are the most rewarding. Thereafter the yield levels off for a few years and then gradually declines.
Most asparagus strains grown in the United States today are seekling populations selected from the Martha Washington strains developed in the early 1900s. Plant breeders are developing more uniform plants by reporducing highly selected parent clones through test-tube tissue culture.
In the near future, gardeners will be able to purchse these high-yielding uniform seeds or even highly selected, extremely productive clones propagated by tissue culture.
The underground root system of asparagus consists of an extensive network of fleshy storage roots with small feeder roots that absorb water and nutrients. The storage roots are about the diameter of a pencil and may be five to 10 feet long on mature plants are growing.
Through photosynthesis, the mature plant produces carbohydrates and synthesizes other essential nutrients that are translocated to the storage roots. The stored reserves supply the enregy required to produce spears during the following growing season.
It is important to protect the fern-like foliage from injury during the summer, and to prevent weeds from competing for moisture and nutrients. Watering the asparagus during dry weather in the summer can pay big dividends.
Asparagus can be planted along a fence as long as there is plenty of sun. In fact, the beautiful green fern-like foliage grows five to six feet high and can be used as an ornamental summer screen.
The soil for asparagus should be only slightly acid (pH between 6.5 and 6.8) and should be well supplied with organic matter such as manure or compost. The plants lose vigor, become more susceptible to root rot and die in poorly drained soils or following prolonged high rainfall.
A 50-foot row should be adequate for a small family (about 40 plants) but more will be required if you want to freeze some for use later on.
To start your asparagus, you can buy seed or 1-year-old crowns. The big advantage of the crowns is that you can start to harvest a year sooner.
Here is a favorite recipe for cooking asparagus: Tie the stalks into individual servings and then stand the bundles in a deep saucepan in rapidly boiling salted water one to two inches deep. Cook uncovered for 5 minutes, then cover and cook 5 to 15 minutes longer, or until tender. The rising stem cooks the tender tips while the boiling water cooks the stalks.