How Cranberries Grow: Winter

Winter flood

Cranberry bogs are flooded from late December through mid- March depending on the weather, to protect the vines and buds from winter injury.


A layer of sand is applied to the cranberry bog every few years. This cultural practice is done to stimulate growth, improve drainage and control weeds, insects and fungi. Sand can be applied in several ways. With dry sanding, sand is applied directly to the vines by a bog vehicle or by hand. In ice sanding, the sand is applied on the ice that forms on the winter flood. The third method is barge sanding, where sand is applied by using a barge on a flooded bog.

See the Ice Sanding page for more information.

Equipment maintenance and Construction

Since there are fewer than 1,000 cranberry growers in North America, large companies do not manufacture farm equipment for cranberry production. Most growers use the winter months to design, build and maintain their own equipment.

Brush cutting and Tree clearing

Growers often will remove brush and trees around the perimeter of the bog to promote air movement which helps reduce frost risk and cuts down on fungal growth. Removing brush and trees that serve as alternative hosts for weeds diseases and insects also helps cut down on pesticide use.

Grower Education

Through continuing education workshops, growers spend many hours learning the latest environmental and production related practices that will increase the efficiency and environmental compatibility of their operations.