About 15 to 20 Suffolk citizens are oyster gardeners, the Nansemond River Preservation Alliance estimates, but a workshop on Saturday aims to boost those ranks.

Cindy Pinell, in charge of the alliance’s citizen growers program, says the workshop will show folks how to build the special floats in which oysters are raised.

The Taylor Float Construction Workshop will be held at the CEH Ruritan Center on Eclipse Drive from 9:30 to 11:30 a.m.; it’s open to both those who want to build a float and general volunteers.

“Anybody can come out and learn how to build a float for themselves,” Pinell said. “If they live on the water, that’s great,” or they may be able to arrange to grow oysters off a friend or family member’s dock.

Pinell grows her oysters off fellow alliance member Karla Smith’s dock. One float, Pinell said, can handle 2,000 to 4,000 oysters when two oyster bags are alternated.

Taylor Floats are constructed from PVC pipe, coated wire mesh and zip ties. They come in two sizes.

Pinell said it costs about $150 to construct a two-by-three-foot float. Workshop participants hoping to go home with a float of their own will have to bring the money with them on Saturday.

After the initial outlay, the annual cost to keep a Taylor Float producing is about $40, she said.

Inside the bags, baby oysters grow about an inch per year. If growing the mollusks to eat, one has to wait until they’re at least 3 inches; otherwise the oysters are generally “planted” earlier on reefs in the Nansemond and tributaries.

The alliance plants its oysters in June. This past June, 35,000 of the water-rejuvenating mollusks, many grown by school groups, were planted in the Nansemond and Chuckatuck Creek.

An adult oyster can filter 50 gallons of water a day. Experts say that when John Smith arrived, the oyster population could filter the entire Chesapeake Bay in one week. But 400 years later, it takes an entire year.

An average-size dock can handle six or eight floats, Pinell said, and oyster growing is becoming more popular.

“More people see the floats on their neighbors’ yards and they come and ask what they are doing,” she said. “The word-of-mouth has been spreading, and we’re getting more people involved.”

The water quality of the Nansemond closer to Suffolk is too poor to support oysters, Pinell said, but they can be planted further along the river, and “it’s going to lead up and clean those areas.

Pinell said that Saturday’s event will have enough material for 20 floats. To register, call Elizabeth Taraski at 708-6114 or email etaraski@gmail.com.