By Kathy Conner Cornell
Whether you make your own sauce or push it out of an Ocean Spray can, cranberry sauce is a staple at our holiday tables. In commercials, we often see people in waders standing in thigh high water surrounded by floating cranberries. This might be the scenario for a commercial grower. But with proper care, the home gardener can grow cranberries.
No matter how you like your cranberry sauce, cranberries are a small bush suitable for growing in our gardens to harvest your own fresh cranberries.
Photo by Bill Cornell
Cranberries, Vaccinium macrocarpon, are in the heath family and are related to blueberries and huckleberries. They are evergreen with attractive leaf color in all seasons. As with blueberries, cranberries need acidic soil. Elemental sulfur and gypsum can be used to lower pH. Soils in Southside are naturally acidic so doubtful that change may be necessary. North Carolina Extension suggests <6.0. Soil test kits are available from your Virginia Cooperative Extension Office as hand held meters are rarely accurate.
However, since most of us have clay soils, adding organic amendments such as shredded leaves, compost and composted manure will help to increase soil drainage – another need to grow cranberries. DO NOT add sand. I have seen this recommended but it is a bad idea. Soil has pore spaces that hold air and water needed by the plants. Think of clay particles as a grain of rice and sand particles as a beach ball. Throwing beach balls into rice grains will clog the pore space and make a nice brick.
Cranberries also require a chilling period which our winters will provide. I checked the USDA Plants Database and there are only 2 places where cranberries are native in Virginia. One is in the mountains in Giles, Augusta, Grayson and Carroll counties and the other in Tidewater. Most commercial growers are in New England. However, the plant is hardy from USDA Hardiness Zones 2 to 7, our zone. Cranberries also need full sun.
Although our picture of cranberries is floating in water, the plants will not thrive with constantly saturated roots. They like moisture but require well-draining soils. Their wetland indicator is OBL which means they almost always occur in wetlands. You can provide the moisture with a weekly soaking of 1” if there has been no rain to compensate. You can grow cranberries on a stream or pond bank. The plant can take periodic flooding.
Pilgrim, Stevens and Early Black are the cultivars available to home gardeners. Seeds can be purchased and that process will take the patience of Job. I would suggest purchasing small plants. I was surprised at the offerings on that infamous mail order site. It is best if you can purchase a plant that was grown within 200 or so miles of your residence. This will help ensure the plant will be happy in your environment.
Cranberries are more of a ground cover and tend to send out runners similar to strawberries. Getting only about 1.5’ high, they are suitable to be grown in a large pot. Be sure to have a drainage hole and raise the pot up about ½” to ensure good drainage. I find a wine cork, cut into 3 pieces crosswise, works well to raise the pot. The cork can take quite a bit of weight. In Dr. Michael Dirr’s Manual of Woody Landscape Plants, Dirr says that he has successfully grown cranberries in pots. He uses a ½ potting soil with ½ sphagnum peat moss mixture. Peat moss is not a sustainable product so I suggest using coconut coir instead.
According to North Carolina Extension, the flowers are “showy small fuchsia pink … develop from stem tips. Each bloom has four thin white petals that are acutely reflexed, exposing a dark, elongated central cone of 8-10 fused stamens. They bloom from May to July”. It will take 3 years to get harvestable berries. No, you don’t have to flood your yard to harvest the berries. Cranberries should be harvested when the berries are an even color red and semi-soft to the touch. Clare Groom of The Gardeners Path suggests the bounce test. If you drop a berry and it bounces back, it is ready to be harvested. Unripe berries, like figs, will not mature off the bush. She also suggests that if you can wait to harvest after a couple of light frosts, the fruit will be sweeter. Gently pick the berries off the shrub.
There are many ways to preserve cranberries. The berries can be frozen. To keep the berries separate, place on a baking sheet and freeze for a few hours and then put into zip lock bags. Drying is also an option. Some of my friends have said they put what they want to dry on a cookie sheet and place it in the car wind shield facing the sun. I am lucky to have a dehydrator. Drying in a warm oven is also effective. Of course, you can make jams or relish.
The Virginia Cooperative Extension Halifax Extension Office is open from 8 a.m. to 5 p.m. Monday-Friday. If you have gardening questions, you can continue to reach an extension master gardener or extension staff member by sending an email to firstname.lastname@example.org or calling the Halifax Extension Master Gardener Help Desk at 434-830-3383. Be sure to give us your first and last name, telephone number and the nature of the call. The help desk phone is routinely checked Monday-Friday. Someone will get back to you, although it may be from a different telephone number. Think about trying cranberries this spring, they also have good fall color and attract many pollinators.