Seaweed and grass clippings both make good compost items for gardens. Each of them has a series of individual benefits
Grass clippings are a commonly-used compost item simply because they're free and easy to access. Grass is rich in nitrogen and composts into particularly good soil. When added to a compost pile, it should be used sparingly and mixed in well to avoid clumping.
Using grass in compost piles also saves on tipping waste after lawn cutting. Cuttings are simply recycled and reintroduced into the ground.
Individuals with access to seaweed will already know it is one of the best compost items available. Seaweed is packed with nutrients which will produce a high quality soil when composted. Rinse seaweed off before use so that excessive salt doesn’t get introduced to your garden.
However, one must consider the impact of moving seaweed from its own environment. Many organisms and forms of bacteria that are beneficial to marine life live in seaweed, and continually removing these life forms can eventually have a devastating effect on the environment.
Both seaweed and grass clippings are good for the gardening and soil. Seaweed is richer in important nutrients, but grass is more readily available, and has a lesser impact on the overall environmental structure.