NewsProtecting Paradise


Seaweed as fertilizer? One man found a use for seaweed miles from the beach

Posted at 9:59 AM, Aug 08, 2019
and last updated 2019-08-08 10:11:14-04

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If you've been to the beach recently, you probably had to walk or swim through seaweed, and a lot of it!

The sargassum seaweed washing up on our beaches is a nuisance and an eyesore, but now one South Florida man has found this seaweed is pretty useful miles away from the beach.

Dennis de Zeeuw came up with the idea while seeing seaweed in Central America. "Someone should pick this stuff up and make some money from it," he said.

As the owner of Sustainscape landscaping business,he turned his attention to using it as a fertilizer.

He started with the yellowing and struggling slash pines at the Morikami Gardens in Delray Beach, and in no time they turned vibrant green. "One of things we're noticing is that the effects we’re seeing are faster, that's the biggest thing is we're seeing a faster response from the plants," said de Zeeuw.

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He says he's using the sargassum as part of a fertilizer he's developing. No one is quite sure yet what it is about the seaweed that works, but they know it works organically without the nitrogen that is suspected of causing algae problems.

"I think using a natural product in a more fermented state, really the results we're seeing are amazing," said Heather Grzybek with Morikami Gardens.

The next step, de Zeeuw says is to see if the sargassum can help a wide variety of plants. "I think it's going to work better with the more research we do with it."

If it's proven seaweed can help other plants, then it's also possible to think private industry may be coming to remove the seaweed off the beaches and help keep Florida green.