Biostimulants are non-nutritional growth enhancers. These products aim to increase the growth of roots, leaves or to increase tillering with stolons and rhizomes. Another objective is also to improve resistance to different types of stresses beyond the objectives that are achieved by normal tillage.
Biostimulants provide growth promoters.
The formulation of these products usually contains:

- Phytohormones
- Carbohydrates and humic acids
- Micro-organisms
- Proteins and amino acids
- Enzymes
- Vitamins
Sometimes, to enhance the effect of growth promoters, they may have small additions of iron o nitrogen.
Under normal conditions the ratio of hormones always results in growth stimulation, but under stressful conditions such as short mowing or heavy trampling the ratio can become unbalanced. In this unbalanced situation the application of biostimulants starts to make sense.
Commercial test results do not always take into account all variables that influence turf growth.
In each species the optimal proportion of hormones may vary, so that a product may cause effects of different intensity with the same application. It has been found that biostimulants have a greater effect on surfaces that suffer from stresses such as high or low temperatures, drought, salts...
The best products on the market are always associated with university studies or go hand in hand with studies of the populations of micro-organisms living in the soil. It is always recommended to test in the field to find the differences between similar areas and to determine that the product has favourable reactions in the field.