Jun 28, 2018
Tank mixing – the effective application of macro- and micronutrients
Applying macro- and micronutrients via foliage is good agricultural practice. The water-soluble products EPSO Top, EPSO Microtop and EPSO Combitop can be used to increase yields and quality or as a quick remedy for latent magnesium, sulphur, boron, manganese or zinc deficiencies.
The “Jar Test”
To save time, many users commonly mix these foliar fertilisers with other products to form a tank mixture. Manufacturers seldom provide sufficient information about possible combination and mixtures with pesticides. Therefore, particular attention should be paid when tank mixing. The so called “Jar Test” is a cost-effective and fast method for testing the miscibility of various products. Solutions of the respective products are added to a sealable, transparent vessel one by one and shaken vigorously.
Note the order of the mixing partners, water temperature and mixing process
In preparing a tank mix, care should be taken to ensure that the mixing components are added to water in the right order: Solid substances are added first, then suspensions and finally, dissolved agents. The water temperature should also be taken into account. In general, a product from the EPSO family will dissolve faster the higher the water temperature is. In practice, a range of 20 – 25° C is ideal. In the case of water temperatures below 12° C, lower concentrations should be chosen (e.g. 1 – 2 % w/v) and care should be taken to ensure proper mixing. If the mixing partners combine together well, no flocculation or precipitation as well as a marked discoloration, increased frothing or any other reaction should be visible in the mixture. However, a milky turbidity can be normal when certain pesticides are used.
Check pH value
In addition, substantial changes in solution pH can occur when boron or manganese are mixed with insecticides of the pyrethroid group. If needed, a test can be performed with pH strips and the solution tested on approx. 1 m² of crops with a hand sprayer.
Please note: the general safety advice on user protection and hazardous substances directives must be observed.