Asparagus plants are long-lived and can produce delicious, nutritious stalks for 20 to 25 years, depending upon the variety. A little slow to begin their productive lives, asparagus can take up to three to five years to thank you with edible rewards for your care. Proper maintenance while the plants are becoming established will ensure bountiful harvests for many years to come. These plants need at least 7 to 8 hours of full sun daily to thrive, along with adequate food, water, soil conditions and excellent drainage.
Prune any trees or other large plants that rob your asparagus seedlings of sunshine. Plants that don't receive enough light will be stunted, more susceptible to disease, and won't produce well.
Amend the soil with peat moss or well-aged manure in the spring and fall each year. Asparagus seedlings need nutrient-rich media to thrive.
Test the soil for pH levels several times throughout the growing season. Asparagus plants grow best with a range between 6.5 to 7. Adjust as needed. Asparagus doesn't grow well if pH drops below 6.0.
Water asparagus seedlings deeply, enough to moisten the top 1 foot of soil once weekly during their first year. During their second year, less moisture will be required and you should only need to water about once every other week.
Mulch asparagus seedlings about 2 to 3 inches deep with organic matter such as shredded leaves, pine needles, grass clippings or straw after foliage. This will be a big help with moisture retention and weed control. Seedlings will have no problem pushing up through the mulch the following spring.
Feed asparagus in late January to early February with a 10-20-10 fertilizer before spears emerge from the soil. Repeat the application in the fall after harvest time. Add a 21-0-0 ammonium nitrate feeding at this time, as well.
Remove and dispose of old foliage when it dies back in the winter. This will go a long way in preventing infestation by asparagus beetles, the most commonly encountered pests.