STILLWATER – Although Oklahoma just experienced one of the warmest Octobers in state history, gardeners still need to be thinking about and preparing to winterize their small fruits gardens.
Small fruits gardens, including blueberry, raspberry, strawberry and blackberry plants, will benefit from a fresh layer of mulch to conserve soil moisture and regulate temperatures over the winter, said David Hillock, Oklahoma State University Cooperative Extension consumer horticulturist.
“When winterizing your garden, apply a 4-inch-deep layer of organic mulch around the base of the plants,” Hillock said. “Organic mulches such as leaf compost, pine bark or straw will provide your plants the insulation needed to prevent cold damage and excessive drying of the soil.”
Adding extra mulch also is beneficial for fruits such as kiwi and grape vines. Be sure to inspect your gardens after the first killing frost and replenish mulch as needed.
Strawberry plants should be mulched in early to mid-December to protect the crowns from winter’s freeze and thaw cycles. Freezing and thawing of the soil damages the growing point of the plant.
“This cycle also can cause soil heaving, which can push the plants out of the ground. This is especially a problem for shallow-rooted plants such as strawberries,” he said. “However, if the warmer weather continues, hold off on mulching the plants until there has been several hard frosts. By this time the plants have developed cold hardiness. If you cover them too early, they may not become hardy enough to withstand winter temperatures.”
Another small fruit gardeners may grow is passion fruit. These plants typically die back to the ground in winter, but will continue to ripen fruits until the tops are killed out.
Following a hard frost, cut the stems back to the ground and cover the plants with a thick layer of mulch to provide winter insulation.
If gardeners notice a mole or rodent problem, pull the mulch back a bit from the trunk in an effort to avoid creating a favorable feeding spot for these pests.
“Taking the time to winterize your small fruits gardens will help ensure your spring gardening gets off to a great start,” Hillock said.