Asparagus is a perennial vegetable that can produce spears for 15 to 30 years from a single planting, making its initial establishment a long-term investment. Most home gardeners begin with one-year-old bare-root crowns rather than seeds, which significantly reduces the wait time for the first harvest. Successful cultivation of this long-lived crop requires careful planning, particularly regarding regional timing and meticulous soil preparation. This guide provides the necessary steps for establishing a productive asparagus patch in Ohio.
Optimal Timing for Planting in Ohio
Early spring, immediately after the soil becomes workable following the winter thaw, is the optimal time for planting asparagus crowns in Ohio. This window generally opens from mid-April and extends through late May across the state, depending on the specific microclimate. Planting at this time allows the crowns to establish their root systems before the stress of summer heat arrives.
It is important to wait until the soil temperature reaches at least 50 degrees Fahrenheit. Planting into cold, saturated soil can increase the risk of crown rot and stunt initial growth. Ohio State University Extension recommends spring planting over fall planting for better establishment success in the state.
Site Selection and Soil Preparation
Selecting a permanent location is crucial because an asparagus bed remains productive for decades. The chosen site must receive full sunlight, ideally six to eight hours of direct sun daily, and should be placed where it will not be shaded by trees or buildings. Proper drainage is essential, since the fleshy crowns are highly susceptible to rot in waterlogged conditions.
The soil should be loosened deeply, to a depth of 12 to 15 inches, to accommodate the extensive root system. Before planting, eliminate all perennial weeds, such as quackgrass or bindweed, because they become nearly impossible to remove without damaging the established crowns. Asparagus thrives in a slightly acidic to neutral pH range, specifically between 6.5 and 7.5.
A soil test can confirm the current pH and nutrient levels, guiding the application of lime or sulfur to make necessary adjustments. Incorporating a substantial amount of organic matter, such as a two- to four-inch layer of well-rotted compost or aged manure, into the soil before tilling helps improve both fertility and drainage.
The Planting Process and Establishing the Crowns
Asparagus crowns are best planted using the trench method. Begin by digging a trench that is approximately 12 to 18 inches wide and 6 to 10 inches deep. If multiple trenches are needed, they should be spaced four to five feet apart to allow for adequate air circulation and maintenance.
A small, three-inch-high mound or ridge of soil should be formed along the bottom center of the trench. The crowns are then placed on top of this ridge, with their roots spread out and draped down the sides. Crowns should be spaced 12 to 18 inches apart within the trench.
After placing the crowns, cover them initially with only about two inches of soil or a soil-compost mixture. This shallow covering allows the crown to begin growing while protecting it.
As the new spears emerge and grow four to six inches tall, gradually add two more inches of soil to the trench, taking care not to completely bury the young shoots. This process of gradual backfilling continues throughout the first growing season until the trench is entirely level with the surrounding soil.
Post-Planting Care and First Harvest Expectations
The first two seasons after planting are dedicated to establishing a strong, energy-rich root system. Newly planted crowns require consistent moisture; if rainfall is inadequate, provide one to two inches of water per square foot weekly, especially during the first summer. Weed control is extremely important, as weeds compete directly with the young crowns for nutrients and water.
Weeds must be hand-pulled or scraped with a shallow hoe to avoid disturbing the developing, shallow roots of the asparagus crowns. A strict “no harvest” policy must be followed during the first full growing season. Allowing all spears to mature into tall, fern-like foliage is how the plant photosynthesizes and stores carbohydrates in its roots.
In the second year, if the plants show strong, vigorous growth, a light harvest may be taken for a short period of one to two weeks. The first full harvest, which can last up to six weeks, should begin in the third growing season. Once the ferns die back and turn brown in late fall, they should be cut down to the ground either then or in early spring before new growth emerges.