It’s Time for Asparagus to Sleep
If you were wise enough some years back to plant asparagus, you’ve been rewarded with a spring feast. Now it’s time to give your asparagus bed a rest to ensure future harvests.
An asparagus bed planted in full sun in well-prepared and well-drained soil can remain productive for 20 years or more — if you treat it well.
If you want your bed to serve you with an abundance of spears each spring, you must avoid over harvesting. Stop gathering spears by mid-June — now — to allow mature foliage to develop. An abundance of foliage is necessary to replenish the energy in the roots and crowns for next year’s crop.
Extending the harvesting season until July will result in a limited crop next season because insufficient time was allowed for recovery. On the other hand, if you limiting the harvest to just a few weeks in the spring, the bed will expand too quickly, crowding the stems. This problem is corrected by extending the harvest season the following year.
Weeds can be a severe problem in asparagus beds. Keeping up with weeds begins in the spring before the spears appear. Cultivate the beds lightly by using a Nebraska flat blade or a sharp hoe or by shallow tilling. I like to cultivate my asparagus bed the first week in April. We don’t start cutting asparagus spears until mid-April.
Once the stalks have developed and the plants are in full foliage, an onion hoe is ideal for removing weeds. Soon after I make my final harvest in early June, I appliy Preen at the recommended rate. Preen is cleared for use on vegetable crops.
Fertilize or mulch with compost soon after the harvest season. I apply calcium nitrate at the rate of one pound per 100 square feet and then apply a one-inch layer of compost. I also place a trickle irrigation line down the middle of each bed before applying the mulch. The trickle irrigation lines are on a feeder line of their own.
In the fall, do not cut off the stems until the foliage has turned completely yellow. Patience allows all of the nitrogen in the stems to drain down to the crown, where it is readily available for next year’s crop.
As asparagus beds age, they become more attractive to asparagus beetles. Thus far I have never had a severe infestation.
However, in August you are likely to see caterpillars of different colors feasting on the foliage. These are mostly butterfly caterpillars that can most easily be picked by hand each day unless you are interested in promoting butterflies.
The Mystery of Bulb Storage, Solved
Q: –Lucy Goszkowski, Annapolis
A:
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