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Healthy and Sustainable Food
 Asparagus
DATES IN SEASON:
New England: Early-May through early June
Mid-Atlantic: Mid-April through June
BRIEF DESCRIPTION:
Asparagus (Asparagus officinalis, Liliaceae) belongs to the lily family and is a relative of the grasses. Indeed, early colonists in New England called asparagus ‘sparrow grass.’ Asparagus was cultivated during the Roman period and was used medicinally before being eaten as a delicacy. Thought to have cleansing and healing properties, it was used to treat everything from heart trouble to toothaches as well as to prevent bee stings.
The basis of an asparagus bed is an underground structure that grows from seed consisting of thick, fleshy roots joined at the crown. Asparagus spears emerge from the crown, however it is not until the beds have been established for about three years that they can be harvested. Asparagus is harvested by hand (which is why it is relatively expensive) in the spring when spears are 6 to 8 inches high and the tips are still compact. If the spears are left to mature, the stalks will become tall and woody while the head will transform into a mass of feathery foliage. Asparagus beds can produce spears for up to 20 years.
VARIETIES:
There are many varieties of asparagus, but the green Jersey varieties are most commonly found in the market. They are known for their tenderness and consistent quality in taste and appearance. The “Jersey Knight” is found in more moderate climates, while the “Jersey Giant” is available early in the season in colder areas. Stalk diameter can range from thin to very thick. While green asparagus is predominantly sold in the United States, white asparagus is preferred in Europe. White asparagus is the same plant as green asparagus, it is simply covered with soil and grown in the dark before being cut from underground. The stalks are said to have a milder flavor than green asparagus and are more readily found canned in the United States than fresh. There are also purple varieties grown primarily in Europe that have a fruitier flavor.
USING ASPARAGUS:
Fresh asparagus stalks are firm and straight with a rich green color and closed tips. An open tip is a sign of over maturity. Asparagus can be eaten raw with dressing or vegetable dip or cooked. To ensure even cooking times, choose stalks that are similar in size. (There is a great debate among asparagus lovers over which is the more tender shoot, thick or thin. While thicker stalks may need peeling, both thin and thick stalks can have tender, tasty flesh. It is largely a matter of preference). Before use, trim the ends with a knife or by snapping the woody base off by hand. The stalks can be cut or kept whole and are enjoyable steamed, roasted, grilled or stir-fried. They can also be reserved for soups or stock, side dishes, omelets and salads. Cooking asparagus generally takes 5-15 minutes depending on the method – steaming, braising, grilling, or roasting – and size of the stalks. To retain valuable nutrients, do not overcook asparagus.
NUTRITIONAL INFORMATION:
Asparagus is a nutritionally superior vegetable due to its high, diverse and well-balanced vitamin and mineral content. One cup of chopped asparagus provides only 33 calories, but over 2/3 the amount of vitamin K needed for an entire day. It is also rich in beta-carotene and is a good source of fiber, folate, vitamin C, iron, thiamin, riboflavin, copper, and manganese.
STORAGE:
General: Asparagus should be eaten immediately, or kept in the refrigerator no more than 2-3 days. Do not wash the stalks prior to refrigeration, rather snap off the ends and stand stalks upright in a container with 1” of water, or keep them loose in a plastic bag.
Freezing: Asparagus can be kept frozen for up to 8 months. To freeze, trim and leave whole or cut into 2-3” lengths, blanch with steam or boiling water until bright green and still crisp, and submerge in ice water immediately. Dry stalks and seal in airtight plastic bags. Once asparagus has been defrosted, use it immediately and do not refreeze.
Canning: Asparagus, like other vegetables, can be canned using a spressure canner. Asparagus is also well suited to pickling.
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