Of all the fruits and vegetables that are part of the typical Thanksgiving dinner, the one almost nobody grows at home is cranberries. But you could, although not for this year.

Cranberries are a native evergreen ground cover with the botanical name Vaccinium macrocarpon, which puts them in the same family as blueberries. While TV ads show them growing in a bog, in nature they thrive next to lakes and streams. They are flooded to make it easier to harvest them.

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Yes, cranberries used for juice and canned sauce are flooded for the harvest, but the cranberries you use for a cranberry tart or whole-berry sauce are picked dry.

John Harker, co-owner with Debra Parry of Cranberry Creations in the Belgrade Lakes-region town of Mount Vernon, said as far as we know, the first person to grow cranberries in a home garden was Joseph Banks, the prime plant collector in the early 1800s for the Royal Botanic Garden in Kew, outside of London.

I’m writing this column now because this is when people eat/harvest/think about cranberries, but the best time to plant is mid-April to mid-May. That said, they can be planted as late as September.

Cranberries grow best in an acidic, sandy soil. Unless you are starting with those conditions, Harker recommends marking out a bed that is about 4 feet by 8 feet. You dig 6 to 8 inches of soil out of the bed, replacing it with a mixture of three-quarters peat moss and one-quarter sand. His website (cranberrycreations.com) says the job will need about four (3.8-cubic foot) bales of peat moss.

“If you already have sandy soil, you can just amend that with a lot of peat moss,” Harker said.

You also should add fertilizer. Harker recommends a half pound of bone meal, a cup of epsom salts, and a pound each of rock phosphate and blood meal. After that initial preparation, cranberries need little fertilizer.

You will put six to eight cranberry plants into the bed, and in time that will give you three to seven pounds of cranberries each year.

Cranberry Creations sells two varieties of cranberries, offering 2- or 3-year-old ready-to-bloom plants in 1-gallon pots. Stevens is a hybrid bred by the U.S. Department of Agriculture for high production and disease resistance. Howes is a heritage variety, which has more pectin, is brighter red and stores better.

Fedco sells Stevens; Estabrook’s in Yarmouth offers three varieties on its website, and the O’Donal’s catalog offers cranberries but does not specify which kind they are. Other garden centers probably sell them as well.

If you want to plant more than one variety, keep them in separate beds, Harker advised.

After you have grown cranberries for a few years, you’ll have to deal with the cranberry fruit worm, according to Charles Armstrong, a cranberry specialist with the University of Maine Cooperative Extension.

“It’s pretty much inevitable that it will show up, because it does exist as a native insect that has been here since cranberries have,” Armstrong said.

As an adult, the insect is a small, dull brown moth that can fly great distances and detect cranberries. When the berries are about the size of a garden pea, the moths lay their eggs on the cranberries – one per berry. As soon as the eggs hatch, the caterpillars burrow into the fruit, destroying it and making it hard for insecticides to hit them unless the applications are timed perfectly.

The moths fly only at night, however, so home gardeners have an advantage. If you cover the plants with a floating row cover (Reemay) overnight, the moths can’t land on the cranberries in the first place. Remove the row cover during the day, and the flowers can still be pollinated.

Armstrong said organic cranberry growers who don’t spray will lose about half their crop in a bad year to cranberry fruit worm, and that bad years occur about once a decade.

Armstrong said he planted a cranberry bed at home following Harker’s method, and it has produced well – even though he has pretty much ignored it. He advises gardeners to water if it gets dry, and to put most of the sand in the peat moss/sand mixture near the top because otherwise the peat moss will float when you water. The website for Armstrong’s office, umaine.edu/cranberries, offers additional information.

In commercial beds, the cranberries are kept underwater for the winter. Although cranberries are hardy to Zone 3, the leaves dry out if left bare. That means you have to provide winter protection.

“I used to tell people to mulch with pine needles,” Harker said, “but now I advise that they use a sheet or two of Reemay or white plastic.” You don’t have to top the plastic with any other kind of mulch, but you might want to leave some mouse traps or mouse bait, because mice can get in and damage the plants.

Cranberry beds can last for decades, but they do need some maintenance. If you allow grass and/or weeds to get established in the bed, it will be hard to get rid of them. Also, Harker recommends adding a half an inch of sand to the bed every few years and working it down around the roots.

Eventually, you will have to prune.

“If the plants get old and stop producing, you rake all the vines in one direction and cut off all of the long runners,” he said. “If it really gets out of control, you can mow it down to a couple of inches and then let it come back.”

In addition to selling cranberry plants for home gardeners, Cranberry Creations sells fruiting cranberry plants to be used as decorative centerpieces. If you buy or are given one of those, you can wrap in a plastic bag, put it in the crisper drawer of your refrigerator or in an unheated garage, and plant it next spring.

It’s a way to get double the pleasure out of your purchase.

Tom Atwell has been writing the Maine Gardener column since 2004. He can be contacted at 767-2297 or at tomatwell@me.com.