How troublesome sea lettuce is being transformed into plant food on P.E.I.

A P.E.I. entrepreneur is working on a project that he hopes will get rid of a perennial Island problem and help grow interest in the haskap berry on P.E.I.

Extract being tested on haskap berries this summer

Sea lettuce before it goes through the extraction process in a lab at UPEI. (Randy McAndrew/CBC)

A P.E.I. entrepreneur is working on a project that he hopes will get rid of a perennial Island problem and help grow interest in the haskap berry on P.E.I.

Mike Cassidy is working with the UPEI Faculty of Sustainable Design Engineering to develop a liquid bio-stimulant from sea lettuce that can be used to help plants grow better.

Sea lettuce is a problematic algae that grows in large blooms or patches in the water every summer in Island waterways, fuelled by an excess of nitrates in the water from farm runoff, septic tanks and golf courses. 

When the sea lettuce dies it uses up oxygen in the water, creating anoxic conditions that are deadly to marine life.

Cassidy has been trying to find a financially viable way to get rid of sea lettuce for years.

A thick bed of sea lettuce coats a riverbank in 2013. (CBC)

"In 2011, I was the person who took a sea lettuce harvester up from Florida and we were in Covehead Bay and up in Mill River trying to remove sea lettuce from our tributaries and our rivers," Cassidy said. 

"We all know we had an environmental problem in 2011 and we still have the same environmental problem."

At the time, the sea lettuce was spread on fields as part of a pilot project with Agriculture Canada but the process was not sustainable.

In 2011, Mike Cassidy brought a sea lettuce harvester from Florida. (CBC)

"The sea lettuce harvester is a great mechanism to harvest sea lettuce, but we did not have a value-added product for the sea lettuce," Cassidy said.

Extraction process

Now Cassidy is working with Dr. Bishnu Acharya at UPEI on a pilot program which takes the sea lettuce algae through an extraction process.

The first step is to grind the sea lettuce. (Randy McAndrew/CBC)
UPEI Masters student Ankita Shrestha pours the ground-up sea lettuce into the system, which uses a hydrothermal process to create the extract.
The sea lettuce extract was tested on tomato plants and kale plants at the Dalhousie University agricultural school over the winter. (Randy McAndrew/CBC)

"That takes the sea lettuce down to a liquid and we feel it's a value-added fertilizer," Cassidy said.

Acharya and his team have been collecting sea lettuce at Covehead Bay and processing it in a laboratory.

"Once we get the sea lettuce, we will grind them and then put them into our process, which is a hydrothermal process," Acharya said. "We process that at a certain temperature and pressure and finally we get the process extract."

Testing on plants

The extract was tested over the winter at the Dalhousie University agricultural school in Truro, N.S.

Cassidy has planted four hectares of haskap plants. (Randy McAndrew/CBC)

"We have already tested the sea lettuce extract on tomato plants and kale plants and other kinds of plants," Acharya said.

"It has shown a very positive result to work as a bio-stimulant which is helping to grow the plant better."

Now the sea lettuce extract is being tested on haskap plants at Cassidy Farms in Hampton, P.E.I.

The researchers gathered sea lettuce from Covehead Bay to make the extract. (Bishnu Acharya/UPEI)

"Once that is proven, then we are planning to scale up our process and then we want to produce more so that we can do more trials next summer," Acharya said.

If that goes well, commercial sales could begin as early as next summer, he said. 

Growing haskap industry

Cassidy has planted four hectares with 10,500 haskap plants and is eager for the results of the scientific research.

The sea lettuce extract is being tested on haskap plants at Cassidy Farms in Hampton, P.E.I. (Randy McAndrew/CBC)

"We feel that the sea lettuce is a tremendous enhancer," Cassidy said. "Speaking to the professors at Dalhousie and UPEI they are hoping by September we should be able to see some research signs if our sea lettuce enhanced the field crop."

Cassidy is also doing other research to make the case for haskap berries, including different kinds of netting to protect the berries from birds.

"We have no deer, we have no moose — because elsewhere, I just came back from Nova Scotia last week, their fear during harvest season is birds, deer and moose," Cassidy said.

"If we can eliminate the birds, or allow the birds not to take too much of the crop, then I think we're into a very, very good position for haskap on P.E.I."

Nutrients from run-off and septic systems and nitrates from farmers' fields all cause the growth of sea lettuce. (Laura Chapin/CBC)

Tart-tasting haskap berries — which look like elongated blueberries — are beginning to gain recognition for their high antioxidant content, unusual flavour and ability to flourish in harsh weather.

Cassidy also sees the business potential in the sea lettuce extract. 

His company The Cassidy Group recently purchased VanKampen's Greenhouses in Charlottetown.

If the extract research goes well Cassidy is hoping to have it available for sale at VanKampen's as early as next spring.

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About the Author

Nancy Russell has been a reporter with CBC since 1987, in Whitehorse, Winnipeg, Toronto and Charlottetown. When not on the job, she spends her time on the water rowing or walking her dog.


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