Inga Potter and Krista Rosen started a kelp farm in southern Maine in 2021 without knowing what they would eventually do with the kelp.
Potter, a marine biologist, had spent much of her career studying animals, including seahorses and large ocean fish. She earned a Ph.D. from the University of New Hampshire and later taught biology and environmental science. Her interest in kelp came from learning about seaweed farming and its effects on the marine environment. Kelp requires no fertilizer, freshwater or farmland, and while it grows it absorbs nutrients such as nitrogen and phosphorus from the surrounding water.
Potter began talking about the idea with Rosen, a longtime friend. Rosen had grown up in Maine, studied government and economics at Bowdoin College and spent years practicing securities law in New York and Maine. She had also served on the board of the Laudholm Trust, which supports the Wells National Estuarine Research Reserve. During walks together, Potter talked about her growing interest in kelp farming. Rosen began looking into what they might be able to make from it.
Most farmed kelp in Maine was being grown for food. Rosen’s research led her elsewhere. She found studies on the use of compounds from seaweed in cosmetics and skincare, much of the work coming from outside the United States. The two began to consider whether they could grow kelp themselves and use it as an ingredient in skin products.
Neither woman knew how to run a kelp farm. They sought advice from people in Maine’s aquaculture industry, including a local harbormaster, while working through the permits needed to put a farm in the water. They attended webinars and industry meetings and contacted people already working in aquaculture. Their farm was established off Kittery, where lines suspended beneath the surface hold young sugar kelp through the winter and spring.
Figuring out what to do with the harvest became a second project. Potter and Rosen wanted to process their own kelp rather than send it elsewhere and buy back a prepared ingredient. After harvest, they dried the seaweed in a greenhouse and ground it. Rosen’s uncle, Bob Leipold, a retired chemical engineer with experience in the chemical, biotechnology and pharmaceutical industries, joined them to work on extracting compounds from the dried kelp. Chemist Kirsten Thomas later joined the product-development work.
The group became interested in extraction methods that did not rely on the solvents commonly used in chemical processing. They developed a method for infusing selected oils with compounds extracted from their sugar kelp and used it to formulate a facial oil. Cold Current Kelp began selling KelpGlow commercially in 2023.
The company remained small enough that Potter and Rosen handled much of the work themselves. They farmed and harvested the kelp, dried it and took part in making and bottling the finished products. They also began selling through independent shops in Maine and neighboring states as well as through their own website.
Research became a larger part of the business as it developed. In 2023, Cold Current Kelp received a $300,000 NOAA grant for research into growing nori, a red seaweed, using equipment and practices developed for sugar kelp farming. The following year, the U.S. Department of Agriculture awarded the company a $175,000 Small Business Innovation Research grant to study how to recover useful compounds from Maine-grown sugar kelp. That project tested different extraction conditions and harvest ages and analyzed the compounds produced. Cold Current Kelp also received support from the Maine Technology Institute.
Cold Current Kelp gradually expanded beyond its first facial oil while adding wholesale accounts. Its products are now carried by independent stores, markets and other retailers in Maine and several other states. The company continues to grow its own kelp rather than buying the main ingredient from an outside supplier.
