Strawberries are a delicious treat in late spring and early summer. They are plump and juicy---and easily grown in your backyard. However, you need to take care of your strawberry plants in the winter to ensure a good harvest.
The Need for Winter Care
Strawberry plants are very low to the ground with shallow roots. While the plant is a perennial, the roots are annuals. The strawberry plant has to produce new roots every year from its crown. The roots work their way higher and higher up the crown until it is necessary to add more dirt to keep your plants from having exposed roots. Accordingly, your strawberry plants are very susceptible to frost and the damage it could do.
Preparation For Winter
By the middle of October, you should have your plants thinned by removing the runners, the least hardy of the daughter plants, that leave the mother plant to start their own root system. You can choose the hardiest according to the number of leaves (more is better). Also, remove any that have not rooted, as they will not have enough time to take root before winter damage. With the "daughters" thinned away, the "mothers" can put their energy into producing more buds for spring.
Wait until December or the first hard frost to mulch your strawberry plants for the winter. You want to make sure they have endured cold temperatures (20 degrees F or a half inch of frozen ground) to ensure they will be hardy enough to survive the winter. Then add four inches of loose mulch around your plants. Good mulches include wood chips, straw, pine straw, newspaper, sawdust, or hay. Snow is a natural cover for strawberries, but is unreliable in its timing.
When new green leaves begin to appear on your strawberry plants, remove the mulch. Leave an inch or so under the plants to keep the ground moist and to keep the fruit from dropping on the ground. Strawberry plants are more vulnerable in the spring when they begin to blossom than they were in the winter. Leave the rest of the mulch in the area between the plants to cover up blossoms when frost is predicted. Blankets or sheets can also be used to cover your strawberry plants in case of spring frost.
Other ways to keep your strawberry plants healthy and productive include planting them in well-drained soil where they receive full sun and little wind. Be sure not to plant them where tomatoes, peppers, eggplants, or potatoes have been grown to avoid infecting them with verticillium wilt. Strawberry plants do very well in raised beds where they benefit from being more protected from the elements as well as having moisture without being waterlogged. During the growing season, be sure to water them with about an inch of water a week to ensure thriving plants with plump berries.