There is no denying it! Spring and asparagus go hand in hand. Whether it comes from the garden, supermarket, or farmer’s market, asparagus is perfect for any meal. While asparagus may be a symbol of spring, it can and should be enjoyed year round.
Asparagus is a great source of fiber, folate, potassium, and vitamins K, E, A, and C. (Because it is a good source of vitamin K, those who are on blood thinning medications should monitor the amount consumed.) Asparagus does not contain fat or cholesterol and is very low in calories—just 4 calories per spear and approximately 27 calories in a one cup serving.
Peak season is usually mid-April to early/mid-June in the Midwest depending upon the season. When the temperatures warm in June, the spears begin to get spindly indicating it is time to stop harvesting and let the plants mature into their fern-like foliage and replenish for the next growing season.
Selecting and Preparing Asparagus
Green is the most common color of asparagus. However, it can also be white or purple. White asparagus is green asparagus that has been covered to block out light to the green shoots so that photosynthesis cannot take place. White asparagus has a very mild flavor and because of the extra effort to cover and blanch it, it is usually more expensive. Like white asparagus, purple asparagus also has a mild flavor; it also exhibits a nuttiness and sweetness due to a higher natural sugar content. It is best used raw or cooked minimally as it will turn green with cooking. Purple asparagus is a result of a genetic mutation of a variety of green asparagus; purple has 40 chromosomes instead of the natural 20 found in green and contains anthocyanins contributing the purple color.
Regardless of color, select stalks that are smooth, uniform in color, and have compact tips. Avoid stalks that are shriveled, limp, or have open, seedy tips—all signs of aging or improperly cared for spears. Do a sniff test; old asparagus gets smelly fast.
Asparagus can be prepared in any number of ways—broiled, steamed, grilled, roasted, sautéed, air fried—or used fresh or par-cooked/cooled in salads. Whatever cooking method is used, the cooking time is short as asparagus is easily overcooked. Strive for stalks that are tender crisp.
Wash and remove the woody stems prior to cooking or using fresh. Gently bend the stalk until the woody part snaps away naturally. Peeling is a personal option; some people like to peel the lower stalk or remove the scales when the stalks are ½-inch or larger as the lower stems may be a little tougher.
Storing or Preserving Asparagus to Retain Freshness
Asparagus is best used fresh. Store asparagus spears in the refrigerator with the ends wrapped in a damp paper towel or with the stalk ends in shallow water. Loosely cover with plastic to prevent dehydration. If asparagus has been purchased at the market, cut the stalk ends about an inch before wrapping or placing in shallow water. Asparagus will keep well in the refrigerator for a week or longer using one of these methods. Watch asparagus for signs of spoiling—cloudy water, soft/mushy heads, limp stalks, off odor. If heads are drooping but not soft, remove the head and use the rest of the stalk for soup.
Asparagus can be preserved by freezing, drying, canning or pickling for year-round use. In all cases, young, tender spears should be selected and thoroughly washed. Scales should be removed if the directions/recipe directs such. Blanching is needed prior to freezing or drying. Blanching—scalding vegetables in boiling water or steam for a short time—is a must for almost all vegetables to be frozen. It stops enzyme action which can cause loss of flavor, color and texture; cleanses the surface of dirt and organisms; brightens the color; helps retard loss of vitamins; and makes packing easier. Timing is also critical. Underblanching stimulates the activity of enzymes and is worse than no blanching. Overblanching causes loss of flavor, color, vitamins and minerals.
Freezing. Sort the spears into sizes and cut into even lengths. Water blanch small spears for 2 minutes, medium spears 3 minutes and large spears for 4 minutes. Steam blanching is also an option and takes about 1 1⁄2 times longer than water blanching. After blanching is complete, remove the asparagus from the water and put in ice water. This stops the cooking action and retains color, texture and flavor. After it has cooled, drain and package, leaving no headspace OR tray pack prior to packaging.
Pickling. The addition of vinegar to asparagus increases the acidity allowing for processing in a boiling water bath. The National Center for Home Food Preservation has a tested recipe for Pickled Asparagus. Note that the use of hot peppers in the recipe is optional. Delicate spears enhanced with garlic and dill remain flavorful and crisp.
Drying (Dehydrating). A dehydrator or an oven may be used. To successfully dry asparagus, follow directions by Colorado State Preserve Smart. Watch the spears closely at the end of the drying period to prevent scorching and be sure to condition prior to long-term storage.
Canning. Asparagus is a low-acid vegetable so a pressure canner must be used to guarantee the spears or pieces are shelf safe and free from clostridium botulinum, the toxin that causes botulism. The National Center for Home Food Preservation provides directions for spears or pieces by hot or raw pack.
Make the asparagus season last as long as possible! Store fresh asparagus properly to retain freshness or preserve it to make the season last through the year.
Sources:
National Center for Home Food Preservation
Drying Asparagus, Colorado State Preserve Smart
Preparing and Preserving Asparagus, PennState Extension
Using, Storing, and Preserving Asparagus, Michigan State University Extension
