Asparagus is a perennial vegetable typically planted from crowns, which are dormant, one-year-old root structures. Since a well-established patch can produce for two decades or more, the success of your long-term harvest depends entirely on the proper handling and planting of these crowns. The initial steps, including pre-soaking, are designed to minimize stress and maximize the plant’s ability to establish a robust root system for future production.
The Importance of Hydration: Why and How to Soak Crowns
The answer to whether you should soak asparagus crowns is yes, as it provides a significant advantage for the dormant roots. Crowns are shipped bare-root and are dehydrated, placing them in a state of deep dormancy. Soaking helps to rehydrate the tissues and effectively wakes the root system before planting. This simple action reduces the shock the plant experiences when placed into the soil, promoting faster establishment.
A brief soak in plain water replenishes lost moisture within the root cells. The recommended duration is between 30 minutes and one hour, though some gardeners soak for up to a few hours just prior to planting. Use room-temperature water to avoid shocking the roots with extreme cold. Once the crowns have absorbed moisture, they should be planted immediately to prevent the delicate root hairs from drying out again.
Preparing the Trench and Inspecting the Crowns
Long-term asparagus success requires proper site selection and soil preparation, as the crowns will remain in this permanent spot for many years. Asparagus needs full sun and exceptionally well-draining soil, as the crowns will rot if they sit in standing water. Before digging, amend the soil with a generous amount of organic matter, such as compost or well-rotted manure. Asparagus prefers a near-neutral soil pH, ideally between 6.5 and 7.5, which should be checked and adjusted before planting.
Physical preparation involves digging a trench wide enough to accommodate the spread of the roots. A typical trench is 6 to 12 inches deep and 12 to 18 inches wide; use the shallower depth for heavy clay soils and the deeper end for sandy soils. Before planting, inspect the crowns for signs of damage, disease, or rot. Any visibly broken or mushy roots should be trimmed away with clean shears to ensure only healthy material is planted.
Proper Planting Depth and Technique
The trench is not filled completely at planting time. Instead, form a small soil mound, approximately 2 to 3 inches high, down the center of the trench floor using loosened and amended soil. This ridge provides a solid base for the crown and positions the roots correctly for optimal growth.
Place each crown individually atop a mound, draping the roots evenly down the sides like the spokes of a wheel. Spacing between crowns should be 12 to 18 inches to allow sufficient room for each plant to develop its root system. After positioning, cover the crown with only 2 to 3 inches of soil, ensuring the roots are completely covered while the trench remains mostly empty.
The critical technique for long-term health is the gradual filling of the trench as the season progresses. Once the first spears grow 4 to 6 inches tall, add another 2 to 3 inches of soil around them. Repeat this process several times throughout the first growing season until the trench is completely filled and level with the surrounding soil. This gradual mounding encourages the crown to produce new roots higher up, resulting in a deeper, more securely established plant.
First-Season Care for Establishment
The first season is dedicated to allowing the crowns to build energy reserves necessary for future harvests. Consistent moisture is paramount during this establishment period, as new plants lack the deep root systems of mature asparagus. The patch should receive about one inch of water per week, especially during dry spells, to prevent young roots from drying out.
Weed control is a high-priority task, as young crowns cannot compete with weeds for limited water and nutrients. Shallow hand-weeding or light cultivation is recommended to remove weeds without disturbing the newly forming roots. Most importantly, no spears should be harvested in the first year. Every spear that emerges must be allowed to grow into its mature, feathery fern state. These ferns photosynthesize sunlight into energy, which is then stored in the crown for the following year’s production.