By Sandy Feather ©2010
Penn State Extension
Q. I planted asparagus for the first time this spring. What should I do to prepare them for winter? Should I cut them back? I allowed the ferns to grow all summer, according to the instructions I received when I purchased them. Is it true that I cannot harvest any for three years?
A. Unfortunately for the gardener hungering for a taste of homegrown asparagus, it is true that you should allow them to grow for two years before harvesting any spears, and harvesting very lightly in the third and fourth years. This allows the plants to direct the majority of their energy toward establishing the extensive root systems that will result in a long-lived, productive asparagus patch. It is common for well-established and cared for patches to last 15 - 20 years, or even more.
A rule of thumb is to harvest for two weeks in the third year, four weeks in the fourth year, and eight to ten weeks in following years.
As for preparing asparagus for winter, it is important to allow the tall ferny foliage to die down on its own, just as you would with spring flowering bulbs such as daffodils. Once it is completely yellow and dead, cut it back to two-inch stubs. If the patch has not been troubled with insect or disease problems, the foliage can be composted. Rake off and compost the summer mulch. Replace it with a four to six inch layer of shredded leaves, clean oat straw or composted grass clippings AFTER the ground has frozen.