University of Edinburgh
 

BSL Biology Glossary - fertiliser - definition

Definition: This can be natural; like manure from cows; or man-made. Both have 1) nitrogen (N) to help plants grow leaves; 2) phosphorus (P) to help plants grow roots, and 3) potassium (K) to help plants grow flowers and fruit. So if a soil is poor in nutrients, people add fertiliser to change the quality of the soil so plants can grow better and more healthily.