Winter can be a difficult time for strawberries in Kansas. Plants need
time to become adjusted to cold weather and will gradually become more cold
resistant as fall progresses. Strawberry plants are able to withstand colder
temperatures in the middle of the winter than in the fall before they have
gone through much cold weather. For example, if temperatures suddenly
plummet below 20 degrees F before the plants harden to the cold, they can be
severely damaged. A drop to 15 degrees F may kill them. Hardened plants can
withstand such temperatures with ease. This lack of hardening off may be a
concern this year because of the unseasonably warm fall. If a sudden drop in
temperature to below 20 degrees F is forecast, it may be wise to mulch the
plants as you would for the winter. After the cold snap is over, uncover the
plants so they may continue to harden off.
Normally, strawberries should be mulched for the winter around
Thanksgiving. However, if temperatures stay abnormally warm, give plants
another couple of weeks to become cold hardy before mulching. Mulching
plants helps protect strawberries not only from low temperatures but also
from heaving damage. Heaving damage occurs when the alternate freezing and
thawing common in Kansas winters heave plants out of the ground where they
can die.
Wheat straw makes good mulch and is widely available. The straw should
be spread over the plants to a depth of 3 inches. Shake the slabs of straw
apart so there are no large compressed chunks. This straw mulch not only
helps protect the plants over winter but can also help avoid damage from
late spring frosts by delaying blooming a few days in the spring. Mulch
should be removed gradually in the spring as plants begin new growth. Remove
enough so leaves can be seen.
Leaving some mulch in place keeps the berries off the ground and
conserves moisture. Also, mulch left in the aisles helps protect pickers
from muddy conditions.
By: Ward Upham
