Jon McGee of New England Sea Farms in Guilford said he harvested roughly 10,000 pounds of sugar kelp on his farm last spring, and he expects to grow roughly five times that volume this year.

THE KELP THEY GROW IS FROM SEEDS STRUNG OUT IN THE FALL, FROM SPOOLS PURCHASED AT BIDDEFORD BASED ATLANTIC SEA FARMS. THIS IS A KELP SPOOL. RIGHT NOW, THERE’S NOTHING ON IT. IT’S JUST BARE.

Wendy Moore, executive director of Lazy Point Farms, an organization that works to help kelp farmers establish and run their own programs, said she has seen interest in sea kelp grow on Long ...