In Costa Rica, fertilizers, biostimulants and soil amemendments are regulated under agricultural laws managed by the Ministry of Agriculture and Livestock, ensuring they meet safety and efficacy standards.
Specific technical standards have been established to guarantee the safety of fertilizers for human health and the environment, covering nutrient content and contaminant levels.
For instance, heavy metal limits are as follows:

Organic amendments, under which many products recognised in Europe as "biostimulants" would fall, must meet minimum concentration limits as outlined in the relevant tables.
Under Costa Rica law, Biostimulants include living organisms such as decomposing microorganisms, nitrogen fixers, solubilizers, and compounds like humic and fulvic acids, amino acids, and vitamins. Soil amendments can be organic (e.g., compost, bioferments) or inorganic (e.g., lime, gypsum) and are used to improve soil properties physically, chemically, and biologically.
Clear labeling requirements mandate that fertilizers provide essential information to consumers, including nutrient ratios and safety precautions. To not too much of a surprise, labels must be in Spanish and provide clear identification of the product, including its purpose and usage instructions.
Biostimulants have to be registered via the submission of a registration application indicating the reason (initial registration or renewal or modification. Registrations are valid for ten years, with specific conditions for modifications and renewals.
The Ministry conducts inspections to ensure compliance with these regulations, monitoring products on the market for adherence to established standards. Actions are taken against any non-compliant products to maintain the integrity of agricultural practices.