Frequently Asked Questions

Out of all fruits, cranberries have one of the lowest amounts of sugar. In every cup of cranberries, there is only 4g of sugar. This compares to raspberries, blackberries, and strawberries, which have 5, 7, and 7 grams of sugar per cup, respectively. Other similar fruits such as cherries and grapes, have 18 and 15 grams of sugar per cup, respectively.

For dried cranberries, these products can be compared to raisins. There is less total sugar in dried cranberries as compared to raisins, but because raisins are naturally sweet, the added sugar is less in raisins than in dried cranberries.

In 1998, researchers from Rutgers University identified the specific components in cranberries that function as previously suggested. These condensed tannins or proanthocyanidins from the cranberry fruit prevent Escherichia coli (E.coli), the primary bacteria responsible for UTIs, from attaching to cells in the urinary tract. Thus, the bacteria are flushed from the tract rather than being allowed to adhere, grow and lead to infection.

Cranberries were recognized by the 2015-2020 Dietary Guidelines for Americans as a nutrient-dense fruit. Just an 8-ounce glass of cranberry juice cocktail contains 137% of the daily value of vitamin C. One of the best-known benefits of cranberries is their use in promoting urinary tract health, but their health benefits also extend through the whole body.

It is vital that growers introduce migratory honeybees and/or bumble bees.  According to Anne Averill, Entomologist with the University of Massachusetts Cranberry Station “Similar to many other fruit crops, bees are needed for adequate pollination.  Cranberry flowers are not capable of self fertilization so pollinators are required to move pollen from one flower to another.”  Several pollination visits are needed to ensure good berry development.  

For more information on bees, see our page on pollination.

During bloom, cranberry growers use one or two beehives per acre of bog. For more information on bees, see our page on pollination.

Typically, it's a 3-day process. On the first day, water is released onto the bog, flooding it with enough water to just cover the vine tips.

On the second day, water reels are driven onto the bog, knocking the fruit from the vines.

On the third day, the fruit is corralled and taken off the bogs with pumps or conveyors into waiting trucks. The trucks then proceed to the receiving station for cleaning and eventual processing.

Fresh cranberries are typically available during the months of September, October and November, which is peak time for cranberry harvesting. Purchasing extra berries when in season and freezing them is the best way to ensure ample supply throughout the year.

Cranberry agriculture is compatible with wetlands preservation. The cranberry is a native wetland plant. Cranberry wetland systems are made up of producing bogs, ditches, dikes, reservoirs, ponds and uplands, preserving over 60,000 acres of open space in the Commonwealth.

Just like natural wetlands, the cranberry wetland system recharges the aquifer; provides flood control and storm-water drainage; protects and preserves habitats for plants and animals; and filters the ground water.

If cranberries are frozen then removed from the freezer then thawed, they will have a soft texture and are usable for cooking and baking. Adding frozen cranberries to recipes is often recommended. Cranberries that were recently purchased and never frozen that appear soft are past the ripened stage, and these berries should be sorted and not eaten.

Cranberries are dicots. They are angiosperms. They have all plant parts (leaves, stems, roots, and fruit) -- the 'runner' is botanically a stolon.

Underground -- the woody part is a buried stolon (runner), the fibrous structures are the actual roots -- cranberries are unique in that they have no root hairs.

Leaves are netted in their venation.

Regarding the fruit -- the cranberry fruit is a berry.

Growers use water for several reasons: irrigation, frost protection, water harvesting, pest control and winter flood protection. The water used in cranberry production is virtually non-consumptive. Water is recycled from section to section and often from grower to grower.
The cranberry harvest takes place once a year from mid-September through early November.

Pesticides are an important part of a typical management plan used in all commercial agriculture including cranberries. In order to minimize pest damage, cultural controls, as well as biological and chemical controls, are used.

Growers weigh the environmental and economic impacts of all control options that are available in order to make the best choice for managing a specific pest. This is called Integrated Pest Management or IPM.

Growers use pesticides only when necessary and when they do, they must be used in accordance with the label directions.

Cranberries are a unique fruit. They can only grow and survive under a very special combination of factors. Cranberries grow on low-running vines in impermeable beds layered with sand, peat, gravel and clay. They require an acidic, peat soil, an adequate fresh water supply, sand and a dormancy period in the winter months that provides an extended chilling period, necessary to mature fruiting buds.
No, commercial cranberry bogs are actually dry. Cranberries require supplemental water from in-ground irrigation systems during the growing season if there is not enough natural rainfall.
Dry harvested cranberries are sold as fresh fruit in poly-bags. About 10% of the Massachusetts crop is picked dry. The other 90% is harvested wet, and this fruit is used to make products such as juice, dried cranberries, and cranberry sauce.

In Massachusetts, all pesticides must be tested and registered for each specific crop use with the U.S. Environmental Protection Agency and the Commonwealth of Massachusetts. Anyone who uses restricted use pesticides must be licensed or certified by the Massachusetts Department of Agriculture, Pesticide Bureau.

Certified and licensed applicators also must complete yearly training requirements in order to maintain their license or certification.

Yes, in fact the cranberry, along with the blueberry and Concord grape, is one of three commercially grown fruits native to only North America.
Those colorful flags mark many things on a cranberry bog. Some mark the edges of ditches or the center line of a bog, to help guide the wet harvesting machines in the fall. Others may mark sprinkler head locations, problem spots, large boulders, or research plots.
Cranberries have four air pockets inside them, which allows them to float to the surface during the wet harvest operation.
There are approximately 13,250 acres of cranberry bogs in Massachusetts, making it the Commonwealth's No. 1 food crop, the second -largest growing region in the United States and the third-largest growing region in the world.
There are approximately 375 growers in the state with the average farm containing about 15 - 20 acres of producing cranberry bog.

In 1816, a retired sea captain named Captain Henry Hall became the first to successfully cultivate cranberries in Dennis, Massachusetts (Cape Cod).

For more information, please see our page on Cranberry History.

Native Americans used cranberries in a variety of foods, the most popular was pemmican - a high protein combination of crushed cranberries, dried deer meat and melted fat. They also used it as a medicine to treat arrow wounds and as a dye for rugs and blankets.
Those yellow/orange vines are a parasitic plant called dodder (Cuscuta gronovii). It is a major weed pest of cranberry bogs, found naturally in swamps of southeastern Massachusetts. Dodder plants attach to a host plant and suck the nutrients out of it.
There are about 4,400 cranberries in one gallon of a typical cranberry juice product.
The name "cranberry" derives from the Pilgrim name for the fruit, "craneberry", so called because the small, pink blossoms that appear in the spring resemble the head and bill of a Sandhill Crane.
It depends on the variety of cranberry but in the most common variety in Massachusetts, Early Black, there are about 440 cranberries.

Cranberries grow on low-running vines in impermeable beds layered with sand, peat, gravel and clay. These beds, commonly known as "bogs," were originally made by glacial deposits.

Normally, growers do not have to replant since the perennial cranberry will survive indefinitely with proper care. Some vines in Massachusetts are more than 150 years old.


Growers use helicopters to reduce the damage caused by driving equipment on the bog. Most helicopter use consists of lifting ditch mud, making crop inspections, applying fertilizer and lifting dry-picked berries.

Some granular herbicides may also be applied with helicopters in the spring but it is not a common practice.