The American cranberry, Vaccinium macrocarpon, is a true North American native that was unknown in Europe until the colonists learned of its virtues from Native Americans. The berries, rich in vitamin C, were a welcome fresh autumn fruit that could be dried for winter use. As a medicine, they were eaten to fight colds and fever and to prevent scurvy. Today, cranberry juice is a known diuretic and is commonly used to treat urinary infections. High in antioxidants and flavinoids, the tart red berries may play a role in preventing cancer.
Cranberries are low-growing evergreens, hardy to Zone 2, that send out runners much like strawberries. Each runner may grow up to three feet long and send up numerous uprights that bear thumbnail-size fruit. The plants thrive in the moist soil along the edges of bogs and wetlands. The ability of cranberry plants to survive under water for long periods of time has helped growers protect the blossoms and berries from spring and fall frosts. Cranberry bogs are constructed so that they can be quickly flooded when freezing weather is predicted. Water is often left in bogs throughout the winter to protect the plants from severe cold.
You don’t need a bog to grow cranberries; in fact, they are a great addition to the home garden. A 5x10-foot plot will yield up to ten pounds of delicious berries every September and October, just in time for holiday sauce and desserts.
For best results, cranberries should be grown in full sun in a 50-50 mix of garden soil and peat moss. If your soil is sandy, remove the top eight inches and line the bottom of the bed with a sheet of six-mil plastic. Poke plenty of drainage holes in the plastic, and then fill the bed with the soil mix. Scratch in one-half pound of 10-20-10 fertilizer, and you are ready to plant.
Cranberries are best planted in late April through the end of May. Six three-year-old plants spaced evenly throughout the bed will grow together to form a thick mat and should produce during the first season. A light mulch of sawdust or sand will help to root the runners. Water the new planting every day for two weeks and then as you would the rest of your garden. Fun to grow and easy to care for, cranberries are one crop that shouldn’t bog down any gardener.