After harvesting freshly picked blueberries all summer, it’s time to put your plants to bed for the winter. Luckily, many berry bushes are cold-hardy and in fact need a certain amount of chill hours to set fruit in the spring.
Dwarf blueberries, such as those from the Bushel and Berry™ collection, can survive during cold months outdoors in the landscape or you may want to put them in an enclosed area. Varieties planted in patio pots generally need more protection since their roots are above ground and less sheltered. Berries planted in the ground need less care; just add a two to three inch blanket of mulch to keep them warm.
Caring for blueberries, raspberries and blackberries in containers over winter is easy. Prevent roots from freezing and cold winds from drying out the plant’s branches with just a little care.
Three steps to overwinter berries in containers and get them ready for spring
1. Give Them a Drink
Many berry shrubs don’t need much water while dormant, but check containers at least once a month. If the soil is dry more than an inch deep, water lightly but don’t soak the soil. If covered with snow, plants will get plenty of moisture.
2. Get out the Pruners
Once berries have been harvested and the plants are losing leaves, it’s time to prune. Plants can be pruned and shaped as long as the shrubs are dormant, even into late winter. Remove any dead or damaged stems in addition to approximately one-third of the lateral stems. While it may seem counter-intuitive, pruning actually encourages fruit growth in the spring.
3. Keep Berry Plants Warm
Most berries grown in containers in USDA Zones 5 and below need to be moved to a sheltered spot when nighttime temperatures drop below freezing—especially during extreme cold spells. An unheated shed, garage, basement or greenhouse will work.
If plants are left outside for the winter, place pots closely together against a shielded part of a building to provide shelter. Pile four to eight inches of straw mulch in and around the pots, but be mindful not to pack mulch against the plants’ stems. Containers can also be wrapped in several layers of burlap or insulating material. Regardless of zone, be aware of any extreme cold spells and provide additional insulation or shelter as needed.
You’ll be thankful you gave your berry plants a little extra attention this winter as soon as you see new leaves and buds forming come spring.