In order to test if raw materials and substrates are plant safe
In order to test if raw materials and substrates are plant safe, RHP can execute a bio assay. To assess the results properly, the achievement of three indicator crops on the product to be tested is always compared to a reference.
With a bio assay it is tested if raw materials and substrates are safe for crops. This is always compared with a reference, often a sensitive crop like lettuce or kale or a standard substrate mixture. Such a reference is necessary for an honest assessment. Various factors can actually influence the growth of a crop.
Assessment of growth
There are various methods to examine substrates and potting soils, however not everything can be determined with a laboratory analysis. A bio assay with test crops can serve as the ultimate test then.
In which situations?
A bio assay can be executed to test the plant safety of a substrate or raw material for a certain crop. Also bio assays are used in the development of new raw materials to test the suitability for substrate application. A bio assay can also be executed to test (organic) fertilizers in a substrate.
How to test?
In case of a potting soil or substrate on which can be sown, the bio assay is directly executed on the growing medium. Dependent on for instance the season, such a trial takes 2 to 3 weeks. If it is a substrate on which cannot be sown, like clay granules, pumice stone, then an extract can be drawn from the substrate and added in a watery fluid to the culture system. In this way it can still be tested if the substrate is safe for the crop.
New substrate or testing raw material?
Do you want to develop new recipes and have executed a bio assay? RHP gladly advises certified companies on this.