Hacker News Reader

Can salt-water-grown seaweed be used as fertilizer? I'd suspect that it would require significant amounts of fresh water processing to remove the salts or else it could hurt the plants.

View on HN

I found a local business that was turning seaweed into fertilizer and he was letting the seaweed dry out and then grinds it up and bags and sells it. I'm not sure if the drying of the seaweed will get rid of the high sodium, but that was my first thought is the amount of work that will have to go into cleaning it.

There also can be other fish, and debris that can get stuck in large patches of seaweed. So that would have to be filtered out as well

I've read rotting fish can be great for gardens... maybe the quantity of fertilizer needed is low enough that salinity isn't a major issue.

Reply on news.ycombinator.com