Starting an asparagus patch is an investment in future harvests. Using bare roots, often called crowns, is the fastest way to begin this perennial journey. Crowns are one-year-old root systems containing the energy reserves necessary to produce spears sooner than starting from seed. Planting crowns instead of seeds typically yields a crop in the second or third spring after installation, shaving a full year off the wait time. Since a well-sited and properly planted asparagus bed can remain productive for 15 to 30 years, getting the initial steps right is essential for decades of delicious spears.
Preparing the Site and Timing the Planting
The longevity of an asparagus patch makes site selection a permanent decision. Asparagus needs a location that receives full sunlight, meaning a minimum of six to eight hours of direct sun exposure daily. The tall, ferny growth that appears later in the season can shade other garden plants, so a spot along the northern edge of a vegetable garden is often ideal.
Well-drained soil is mandatory to prevent crown rot. The soil should be loose and fertile; till or loosen the planting area to a depth of 10 to 15 inches before installation. An optimal soil pH of 6.5 to 7.0 is recommended for strong growth, which may require amending the soil with lime if a soil test indicates high acidity.
It is necessary to eradicate all perennial weeds, such as quackgrass or bindweed, from the planting site before installation. Once the patch is established, weeding becomes challenging without damaging the underground crowns. The best time to plant crowns is in early spring, as soon as the soil is workable and approximately two to four weeks before the last expected frost date. This timing allows the root system to begin establishing itself before the intense heat of summer.
Step-by-Step Bare Root Installation
Once the site is prepared, planting begins with digging the trench that will house the roots. The trench should be approximately 12 inches wide and 6 to 12 inches deep, adjusted based on soil type (shallower in heavy clay, deeper in sandy soil). The removed soil should be set aside, as it will be used to fill the trench gradually throughout the growing season.
A small ridge or mound of soil, about two inches high, should be created down the center of the trench bottom. This mound provides a stable base for the crown and allows the roots to drape naturally downward. The crowns should be spaced 12 to 18 inches apart along this ridge, gently spreading the fleshy roots evenly over the mound’s sides. Proper spacing ensures each perennial plant has sufficient area to develop its large root mass.
After positioning the crown, cover it with only two to three inches of the reserved soil, ensuring the roots are completely covered and the crown’s central buds are buried. The trench must not be filled completely at this stage, as the crown needs to be set deeply over time to protect it from future cultivation. The newly covered crown should be watered thoroughly to settle the soil and eliminate any air pockets around the roots.
As the first spears emerge and grow to a height of two to three inches, add another two inches of soil to the trench, taking care not to completely bury the growing shoots. This gradual backfilling process is repeated throughout the first growing season until the trench is entirely filled to the surrounding ground level. This technique encourages the crown to produce new buds higher up, resulting in deeper, stronger root systems protected from damage and dry conditions.
Immediate Post-Planting Care and First-Year Success
Immediately following installation, the new crowns must be kept consistently moist to encourage fine root growth. Deep watering is necessary, especially during dry periods, to ensure moisture reaches the crown at the bottom of the planting trench. A light application of a balanced fertilizer can be incorporated into the soil at planting time, or a nitrogen-focused fertilizer can be side-dressed after the first shoots appear, but this should be done cautiously.
Aggressive weed control is paramount during the first year, as young asparagus plants struggle to compete for water and nutrients. Since the crowns are still close to the surface early in the season, hand-weeding is often the safest method to prevent damage to the developing root system. Maintaining a weed-free environment allows the plant to direct energy toward establishing a robust, long-term root structure.
The most important rule for first-year success is the prohibition of harvesting any spears. The spears that emerge must be allowed to grow into tall, fern-like foliage, which serves as the plant’s food factory. Through photosynthesis, the ferns produce and store carbohydrates and energy reserves in the crown and roots that fuel the following year’s spear production. Cutting the spears prematurely drains the crown of this stored energy, weakening the plant.