Plant Biostimulant Act of 2025

This bill sets a clear, nationwide definition for “plant biostimulants” under existing pesticide law. It says some biostimulants—those of biological origin or synthetic copies that act like natural substances—are not treated as plant growth regulators. It defines plant biostimulants as substances or microorganisms that help a plant’s natural processes (not just add nutrients) to improve nutrient use, stress tolerance, and growth or yield. It also defines “nutritional chemical” and “vitamin hormone product” to reduce confusion in labeling and oversight.

The Environmental Protection Agency must update its rules within 120 days of the bill becoming law. The Department of Agriculture must study which biostimulants and farming practices best improve soil health, cut runoff of nutrients like nitrogen and phosphorus, and support climate benefits like carbon storage, then publish a report within two years after funds are made available for the study.

• Who is affected: Farmers, farm suppliers, and regulators (EPA and USDA).
• What changes: Clear definitions for biostimulants and related products; EPA updates rules; USDA runs a soil health study and shares results.
• When: EPA updates due 120 days after enactment; USDA report due within two years after funding starts.

Key goals for the study include raising soil organic matter, reducing nutrient loss to air and water, restoring healthy soil life, improving nutrient efficiency, and encouraging practical, results-based approaches that help farms be more sustainable.