Ready your perennial vegetables for winter's wrath

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Last Updated: 
February 19, 2003

EUGENE - Don't forget to winterize perennial garden vegetables this fall.

Rhubarb, asparagus, horseradish, Jerusalem artichokes and artichokes may survive the winter better with a little extra care before winter cold sets in, says Pat Patterson, Master Gardener program assistant with the Oregon State University Extension Service.

Mulch your rhubarb plant with organic matter and well-rotted manure. This assures a good crop next spring.

If your rhubarb is crowded and well established, October is a good time to renovate your plant, a task that needs to be done only every few years. Drive the blade of a shovel down through the middle of the plant. Then remove half of the plant, crown, roots and all. Then fill the hole with compost, rotted manure, or fertilizer mixed with organic matter. Plant the removed half plant to another spot or give it to a rhubarbless friend.

Mulch the asparagus beds with four to six inches of chopped leaves, weed-free straw, hay or similar materials. Next spring, remove the mulch from half of the bed. The asparagus will come up more quickly where the mulch is removed and the mulched section will come up later, thus extending your asparagus season.

Take the mulch off soon after spears begin emerging, otherwise they will curl over. Add some nitrogen fertilizer in the spring.

Horseradish will winter over with no mulching in most places west of the Cascades, and just a light mulching in the colder parts of the state. Horseradish is best and most potent when it's harvested after several good frosts in the fall.

Treat Jerusalem artichokes in the same way as horseradish.

To ensure the survival of thistle-type artichokes (e.g. Globe) clip back the large artichoke rosette. Cover it with six inches or more of mulch, compost or leaves. If there are "pups" coming up around the mother plant, remove the mother plant entirely and protect the pups.

During the harshest part of winter, put a plastic-covered box over artichoke plants. Then fill the box with straw, mounding it over the cut back plant or pups.

Remove the box when the weather moderates. Take away the mulch after most danger of frost has passed in the spring.

Author: Carol Savonen
Source: Pat Patterson