All about biostimulants in horticulture | ICL Podcast

Biostimulants and legislation is the topic for the latest ICL podcast.

ICL’s Sam Rivers says there is confusion about what biostimulants are: micro-organisms that when applied to plants stimulate natural processes. They are not replacements for nutrition or IPM but can help overcome issues in plant production.

Different types of biostimulants include beneficial bacteria and fungi, seaweed, humic and brewer’s yeast-based products and many more; they are described as multivitamins for plants.

Biostimulants work as ‘natural elicitors’, or by inducing plant growth hormones or other methods.

Benefits to using biostimulants in peat-free growing media include adding microbes to sterilised ingredients to boost growth.

Driving the use of biostimulants is EU-wide legal moves to chemical pesticide reduction by 50% by 2030. Sustainable Use Directive hierarchy of controls places biostimulants higher than pesticides, helping result in a shift to biostimulants Europe-wide.

Current legislation on biostimulants in the UK is quite relaxed but they must not claim ‘control’ of pest and diseases or having a fertiliser effect or else they have to be officially registered. Regulations for biostimulants in the EU are stricter with more standards around quantifying claims as a fertiliser. Rivers says this is a good thing as its supports any claims being made and will take “snake oils” off the market as they will need to much work to remain available. The UK could follow suit with the EU at some point.

An example of a product registered under the new standards is ICL’s wetting agent H2Pro TriSmart, now the first registered as ‘non-microbial biostimulant’ under the latest EU Fertilizing Product Regulation (FPR) (1009/2019).