Disposing of the weed by dispersion in agriculture fields is a viable proposition, but this is a volume challenge and labor intensive to prepare as it needs to be collected, rinsed of
salt, cleaned of debris, cut, dried, transported and applied.
An analysis done by the Ministry of Agriculture more than three years ago found that sargassum seaweed had a nutrient content about of about one to 1.5 per cent nitrogen, 0.5 to 1.5 per cent phosphorous, and one to two per cent potassium. It was also pointed out in a
Government Information
Service (GIS) report that that since these nutrient concentrations were so small large amounts of the seaweed would be needed to “experience meaningful results”.
It was also important to note that seaweed has a high
salt content, so that if it were applied directly to the soil, the soil’s alkalinity would increase.
“To treat sargassum seaweed for use as a fertiliser, the salt must be leached. Luckily, this seaweed normally surfaces during the rainy season, and the rain is very useful in diluting the salt from the seaweed. After collecting it from the beach, simply spread it out one to two inches thick and allow at least an hour of continuous rainfall for each inch,” the GIS report stated.
“It is also a good idea to chop the seaweed into smaller particles, as this will allow the nutrients to be released even faster. Composting is another option which makes the nutrients more readily available to plants. The seaweed should not be applied directly to plants. Instead, a drain should be dug between two plants and the seaweed placed along the middle,” it added.