Quick answer
Seaweed washed ashore is compostable and adds trace minerals to soil; most gardeners don't bother rinsing it first, though that advice comes mainly from gardening blogs rather than a government source. Skip seaweed from polluted beaches or near storm drains and sewage outfalls, and check local rules before harvesting living, attached seaweed, since several coastal states regulate that differently from loose drift seaweed.
- Recyclable
- Yes
How to Prepare
- 1Collect loose, washed-up (drift) seaweed rather than pulling living seaweed off rocks, which some states regulate or require a permit for
- 2Avoid seaweed from beaches near storm drains, marinas, or sewage outfalls
- 3Rinse it if using large amounts on salt-sensitive plants or in a dry climate; otherwise it's not strictly necessary
