Off bottom culture means the oysters are grown up off the tidal ground. This method typically uses ground that is soft, where the oyster sinks, or is marginal for growth on the bottom, though it can also be used anywhere. The oysters can also be grown on racks or lines suspended in the water column, not near the ground at all.
We use an off bottom method called long lining, where the oysters grow suspended on ropes that are raised off the ground by pipes. There is a notch in the top of the pipe for the rope to slot into, and the oysters grow in clusters suspended by the rope. All the oysters produced by our farm are “Triploid” oysters. They do not get soft and spawn during the summer months, but remain firm year round.