According to the German Fertilizer Act:

1. Fertilizers: Substances intended to be applied to cultivated plants, directly or indirectly, to promote their growth, increase their yield, or improve their quality; excepted are substances predominantly intended to protect plants from pests and diseases or to influence plant life processes without being intended for plant nutrition, as well as soil conditioners, growing media, plant aids, carbon dioxide, peat, and water.

2. Farmyard manure: Animal excretions, slurry, liquid manure, stable manure, straw, and similar by- products from agricultural production, including after treatment, intended to be applied for one of the purposes mentioned in the first sentence of number 1.

3. Secondary raw material fertilizers: Wastewater, feces, sewage sludge, and similar substances from municipal waste, as well as comparable substances from other sources, in each case also after treatment and in mixtures with each other or with substances according to numbers 1, 2, 3, 4, and 5, intended to be applied for one of the purposes mentioned in the first sentence of number 1.

4. Soil conditioners: Substances without significant nutrient content that influence the soil biotically, chemically, or physically to improve its condition or the effectiveness of fertilizers, in particular soil inoculants, soil crumb formers, soil stabilizers, rock dusts, as well as substances with significant nutrient content intended to be added in small quantities for the treatment of organic material.

5. Growing media: Potting soils, mixtures based on peat, and other substrates serving as a root zone for plants, also in liquid form.

6. Plant aids: Substances without significant nutrient content intended to act upon plants.

7. Manufacturing: The extraction, processing, treating, mixing, and other preparation of substances according to numbers 1 to 5.

8. Placing on the market: Offering, stocking for supply, displaying, and any transfer to others; bringing into the scope of this law for the purpose of transfer to others is equivalent to placing on the market, and transfer within cooperatives or other associations to their members is equivalent to commercial placing on the market.