Asparagus is a perennial crop that signals the start of the spring harvest season. The spears emerge directly from an underground root structure called a crown, which stores the plant’s energy. The correct harvesting method and timing directly influence the plant’s long-term health, productivity, and the quality of the spears. Proper management ensures the health of the asparagus bed for many years.
Determining When Spears Are Ready
The readiness of an asparagus spear is determined by two main factors: the age of the plant and the physical dimensions of the spear itself. Asparagus should not be harvested until the plants are fully established, which generally means waiting until the third spring after planting the crowns. Harvesting too early depletes the crown’s stored energy, which can permanently stunt future production.
Once the bed is mature, spears are ready to be picked when they reach a height of approximately 6 to 10 inches above the soil surface. The ideal diameter is about the thickness of a pencil, or roughly three-eighths to three-quarters of an inch. Spears that grow much taller than 10 inches can quickly become tough and woody, so checking the patch every one to three days is important during the peak season.
Proper Techniques for Removing Spears
There are two accepted methods for removing the spear from the crown: cutting and snapping. The cutting method involves using a clean, sharp knife or shears to sever the spear at or just below the soil line. When cutting below the soil, one must exercise caution to avoid accidentally damaging the underground crown or nearby emerging spears.
The snapping method is often favored by gardeners because it naturally separates the tender, edible part from the tough, woody base. To snap a spear, grasp it near the bottom and bend it until it breaks cleanly at its weakest point. This technique ensures that only the desirable portion is removed, leaving the fibrous section in the ground to decompose without creating a ragged wound that can invite pests or disease.
Managing the Harvest Duration
Managing the length of the harvest window is important for ensuring the long-term vigor of the asparagus patch. For newly established beds in their first harvest year (typically the third year of growth), the picking period must be limited to two to three weeks. A fully mature bed can generally sustain a harvest lasting six to eight weeks.
The primary sign to stop harvesting is when the emerging spears become noticeably thinner, often dropping below the diameter of a pencil. At this point, all remaining spears must be allowed to grow unharvested into tall, fern-like foliage. This fern growth is necessary because it performs photosynthesis, which replenishes the carbohydrates stored in the crown for the next year’s production. Ending the harvest too late will starve the crown, resulting in a weak crop the following spring.
Storing Freshly Harvested Asparagus
Immediate post-harvest handling focuses on retaining the moisture content of the spears to preserve their crisp texture. Before storage, the freshly picked asparagus should not be washed, as excess moisture can encourage spoilage. Instead, trim about a quarter to a half-inch off the bottom of the stems to create a fresh cut.
The most effective short-term storage method mimics how a bouquet of flowers is kept fresh. Stand the spears upright in a jar or container with approximately one inch of cool water at the bottom. To reduce moisture loss, loosely cover the tops of the spears with a plastic bag. This setup should then be placed in the refrigerator, where the asparagus can remain fresh and crisp for up to four to five days.