Get ready for winter gardening at the Community Education Garden

By Connie Mehmel
WSU Chelan/Douglas County Master Gardener
July 6, 2022

Young spinach and lettuce growing in a cold frame.
Spinach and lettuce grown in a cold frame through the winter were producing a crop when this photo was taken in early March. – Provided photo/Connie Mehmel

Connie Mehmel
Connie Mehmel – WSU Extension Chelan/Douglas County Master Gardener – Provided photo

Summer is here, so every gardener knows it’s time to get ready for autumn. With that in mind, the WSU Master Gardeners invite you to the Community Education Garden (CEG) from 10 a.m. to noon on Saturday, July 16 for some tips on winter gardening. As part of the 3rd Saturday in the Garden series, you can learn how to extend your harvest and have a source of fresh greens during cold months.

Cold-tolerant crops can be planted in late summer or early fall under some type of cover for protection from snow and cold, then harvested throughout the winter. Seeds germinate best when the temperature is about 70 degrees F, but some plants will survive quite well in cold temperatures once established. The hardiest vegetables can withstand air temperatures below 28 degrees F. Many cole crops can survive to 10 degrees and spinach can survive down to 0 degrees. Kale, Brussels sprouts, arugula, bok choy and mizuna can be harvested all winter if they have protection from heavy snow.

You can protect your winter crops with low tunnels or cold frames. Low tunnels are made with metal hoops and covered with greenhouse film. They are temporary structures and easy to move, but they can be difficult to manage once the snow arrives.

Cold frames can be purchased or made at home. They generally consist of a wooden frame with a glass or plastic lid that serves as a small, solar greenhouse. During the Third Saturday presentation at the CEG, you will learn how to make a cold frame from salvaged materials.

As the days grow shorter, your winter garden will grow more slowly. Toward the end of October, we reach the “Persephone Period,” named for the Greek Goddess of Spring, when the days are less than 10 hours long and plant growth stops. In Washington, the Persephone Period lasts from Nov. 1 through Feb. 10. Plants can be harvested during this period, but they will not resume growth until the days lengthen.

Besides crops to harvest in winter, you may want to plan for overwintering crops. These are planted in fall, with or without protection, and left in the ground through the winter for spring harvest. Overwintering crops include beets, parsnips and garlic.

Carrots can be overwintered or winter harvested. Last year, I planted carrots in mid-summer. In late fall, I trimmed back the tops and covered the rows with straw bales to keep the soil from freezing. I was able to remove the bales and dig up carrots until heavy snow in January made it impossible to get to the bales. I dug up my last carrots in March, and I am still enjoying them in July.

Many thanks to the Dan and Claudia Goodfellow Foundation for sponsoring this month’s 3rd Saturday at the Community Education Garden.

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