Growing Asparagus
France’s King Louis XIV referred to asparagus as the “king of vegetables” or the “food of kings,” depending on the source. He was the first to cultivate asparagus in greenhouses so that he could enjoy it year-round.
You can also achieve a great harvest by following some simple planting and harvesting tips.
Planting
To achieve the best results, it's recommended to plant one-year-old asparagus crowns to establish a flourishing asparagus bed. In our region, the ideal planting window is between mid-April and late May, once the soil temperature reaches at least 50 degrees Fahrenheit. This timing is essential, as planting too early can hinder growth and increase the risk of crown rot due to cold, wet soil.
When planting, space the crowns 18 inches apart in a single row, and ensure that each row has at least 2 feet of space on either side. To promote healthy asparagus growth, it's important to create a well-draining bed. Research shows that planting crowns too deeply can negatively affect overall yield, so it’s crucial to adhere to the recommended guidelines.
When preparing to plant, dig trenches that are 6 to 10 inches deep. Place a layer of starter fertilizer, such as Bumper Crop Starter Food, at the bottom of the furrow. After preparing the furrow, gently place the crowns in the trench with the roots fanned out and the buds pointing upwards. Avoid packing the soil over the crowns; asparagus thrives in loose soil for optimal growth. Cover the crowns with 2 inches of soil, and as the shoots begin to grow, gradually add more soil until the trench is level with the ground. Water immediately after planting.
Harvesting
Do not harvest the planting year, but cut in following seasons when the width of the emerging stalks are larger than a pencil diameter.
Harvest in the morning when air temperatures are cooler and when spears are 7 to 9 inches tall. Selecting firm, crisp spears with compact tips and tight scales.
Length of harvest season will vary from year-to-year depending on air temperature, stop the harvest when the diameter of 3/4 of the spears becomes small (less then 3/8 inch).
When harvest season is finished, snap all the spears off at ground level.
After Harvest Care
After harvest is completed, apply a high Nitogen fertilizer.
New spears will then emerge, fern out, and provide a large canopy to cover the space between the rows. Once a dense fern canopy is formed, weed growth will be shaded out.
Inspect the ferns throughout the season for insect feeding and fern dieback. Asparagus beetles chew on the fern, causing the stem to turn brown and reducing the yield the next year. Spray the ferns with an approved insecticide when beetles are seen. We recommend Captain Jacks Dead Bug Brew or Diatomaceous Earth, both of which are labeled for Organic Growing.
Do not cut down the fern growth at the end of the growing season. Leave the dead fern growth intact over the winter. This gives your asparagus an added layer of protection.
Remove the old fern growth by cutting or mowing as low as possible during the first week of April in central Ohio.