Spring begins next week. That doesn’t mean we should get overly excited and go clean up our beds just yet, this winter has been long and cold so don’t get too ready for spring. However, Asparagus will soon be emerging from past years plantings and new plantings can soon be started.
Asparagus is a perennial vegetable that will come back every year providing you with more spears without having to plant it every year. Asparagus is planted as crowns in the spring as soon as the soil is dry and can be worked. This year we may have to wait a little longer before planting to give the soil time to dry out after all this snow and rain. Once planted, it is best to wait to harvest from the plant until the third year of growth. Light harvest can be done in the second year, but not all of the spears and not for a long period of time. Asparagus can be planted from seeds, but it will add one more year to the establishment period before harvest is initiated. It is best to give the roots time to become fully established before you begin harvesting. This allows the plant to grow better for longer-lived plants.
Weeds are one of the most common problems for gardeners who grow asparagus. For years, many gardeners used the salt water from making ice cream around the asparagus. Asparagus is a salt tolerant plant and will survive if salt is placed around it and the weeds would die. However, asparagus will not thrive in a high salt condition and the salt can build up and cause asparagus to die over time. Also the salt content in the soil can create a crust which blocks water absorption into the plants which causes drought stress. It is not a recommended practice for weed control.
The better option for weed control in asparagus would be to use mulch around the plants. Any type of organic mulch will work for weed control around the asparagus including grass clippings, wood chips, straw, or hay. This organic mulch will keep the weeds down as well as hold onto moisture and add nutrients back into the soil as the mulch breaks down. Frequent, light shallow cultivation can be done early in the spring will help with weeds as well. Also, use preen that is labeled for use around the asparagus with the mulch to help with annual weeds.
Another tactic is to use a glyphosate product over the bed after the last harvest of the year. As long as the spears have all been cut off at the end of the growing portion of the season and there is no foliage or any green growth above the ground, the glyphosate will not harm the asparagus. Spray the glyphosate over the bed in the late spring when harvest is complete for the year. This will control the perennial weeds as well as the annuals. The spears will then grow back and not be harmed by the glyphosate. Follow up with preen and mulch to keep the weeds out.
Harvesting can be completed by cutting or snapping spears off of the plant as they emerge and grow to 5-8 inches in length. Either method of harvest is fine, I prefer to snap the spears to avoid spreading any disease problems with a knife that just harvested a diseased plant. Snapping is typically preferred by home gardeners. Harvest for 6-8 weeks or until the majority of the spears are less than 3/8 inches in diameter. When all the spears get spindly, the plant is running out of energy for production and harvest should be concluded to allow the plant to rebuild its resources for next year.