Judy Tonderum

Judy Tonderum

Jackson County Master Gardener

It’s holiday time – a perfect time to discuss cranberries. Cranberries have a long history of being an important food for people. Native Americans utilized this bright red fruit in many ways. The berry was used for medicinal purposes; the juice was used for dyeing fabrics and the fruits were eaten in a variety of ways. An important food staple of Native Americans was pemmican, which was mashed cranberries mixed and dried with venison (or meat of the day), fat and grains.

The early settlers soon learned the value of this fruit. It was first called craneberry because the blossom resembled a crane’s head and cranes were often around the fields. Craneberry eventually gave way to cranberry about 1650. By the 1820s, cranberries were being raised by colonists in abundance and were being shipped off to Europe for sale.

Contrary to what most of us thought, cranberries do not grow in water. They grow on woody vines in sandy bogs or marshes. They do not like the warm climate of the South so they thrive in the cooler Northern climates. Cranberries also need acid peat soil, sand and a good supply of water. Blossoms and the berries that follow are produced on upright shoots that are 2 to 8 inches tall. It takes three to five years for a cranberry vine to bear a full crop. Some Cape Cod vines are 150 years old so they live a long life.

Massachusetts was the leading state for cranberry production but Wisconsin has taken over the #1 spot in recent years. Other states that produce cranberries are New Jersey, Oregon plus British Columbia and Nova Scotia. Wisconsin produced more than half of the cranberry crop. Ocean Spray Cranberry Company produced 70 percent of all cranberry products worldwide.

Harvest begins in September and continues through October and November. Cranberries have been on local grocery shelves for the last several weeks. Cranberries were first picked by hand, then with wooden scoops with teeth that combed the fruit from the vine. There are two main ways of harvesting done today. Berries that are earmarked for use as fresh are dry harvested by mechanical pickers with comb-shaped attachments that gather the fruit. Cranberries that are made into juices, jellies, etc., are wet harvested. This is the quicker of the two methods. The growers flood the cranberry bogs with a foot or so of water when the fruit is ripe. Harvesting machines with large reels stir up the water with enough force to loosen the berries. They then float to the surface where they are gathered for transport. In the winter time, cranberry growers flood the bogs and wait for the top 8 inches to freeze. The water underneath the ice is then drained which allows the vines to breath while they are still protected from freezing and drying in the winter air. 

Cranberries are good for you! Cranberries are high in antioxidants, which are thought to help prevent cancer, heart disease and age-related disorders. A chemical compound specific to cranberries inhibits bacteria that cause urinary tract infections, peptic ulcers and dental plaques. Cranberries are considered a good source of Vitamin C, calcium and potassium.

Cranberries can be grown here in Iowa. Several of the reputable seed catalogues offer “No Bog” cranberry plants. The American cranberry is a hardy, low maintenance evergreen ground cover that produced large, tart berries ripening just in time for Thanksgiving. Plants grow 8 to 10 inches tall and 2 to 3 feet wide. It’s a care free, vigorous grower that thrives in acidic soil and is winter-hardy in zones 3 – 7. Its also self-pollinating.

If you are looking for a real handsome shrub for your yard, you might want to consider a Highbush Cranberry shrub. The plant grows eight to 10 feet high and spreads about six feet. Of course, you can keep it pruned down to your desired size. It’s a very popular screening or individual specimen plant. In the spring, the high bush cranberry sports beautiful, fragrant white blossoms, which eventually turn into bright red berries. The leaves are large, broad and deep green. The autumn cold turns its foliage to a beautiful burnished red. The berries are edible but they lack in quality. Birds love them.

High bush cranberry shrubs are hardy in zones 3 – 8 and since we are in zone 5, they survive quite well. I have enjoyed two high bush cranberry shrubs for about 10 years.