Talking Turf

  • Jun14Tue

    The Do's and Don't of Tank Mixing

    June 14, 2016

    Often times, superintendents are applying numerous different products in a single spray solution to achieve various desired results. For example, fungicides and fertilizers are frequently mixed together, allowing for a more efficient use of time and resources when feeding and protecting turf from disease.

    Depending on product chemistry and formulation, problems can arise with incompatibility among mixed products, resulting in coagulation, bound-up product, and clogged sprayer components. Here are a few “best practices” to consider in order to avoid a mixing nightmare in the future:


    Recipe for Successful Mixing:

    • Read the label or contact Manufacturer/vendor if you have questions about materials you would like to mix
    • Do a jar test (i.e. mix commensurate rates of products in a small jar of water and stir (agitate) to gauge compatibility)
    • Fill tank half-way with water before adding materials
    • Agitator should be on
    • Add products to tank SLOWLY and in the correct order (see below)
    • Allow each material to completely dissolve
    • Apply contents of tank within a few hours of mixing
    • Clean tank, lines, and strainers thoroughly

    Formulation Mixing Order:

    1. Water Soluble Packages (WSP’s)
    2. Water Dispersible Granules (WG / WDG’s)
    3. Wettable Powders (WP’s)
    4. Suspension Concentrates (SC’s)
    5. Oil in Water Eumlsions (EW’s)
    6. Oil Dispersions (OD’s)
    7. Emulsifiable Concentrates (EC’s)
    8. Soluble Concentrates (SL’s)
    9. Liquid Fertilizers

    Factors that Affect the Compatibility and Mixing of Formulations:

    • Temperature (air and water)
    • pH of mix water
    • Mixing volume
    • Water hardness (Ca, Mg, etc.)
    • Electrolytes / Fertilizers present
    • Agitation
    • Other pesticides

    Types of Incompatibility:


    • Products separate even with vigorous agitation or as a result of excess agitation


    • High pH can degrade the active ingredient
      • Example: alkaline hydrolysis
    • Low pH can increase availability of some phytotoxic micronutrients such as copper


    • Antagonism – Acclaim + Phenoxy herbicides will reduce crabgrass control
    • Antagonism – some herbicides + non ionics reduce efficacy


    Note:  Aliette Signature has long been a staple in putting green management, and is often used on a regular basis to control various diseases and provide optimal plant health during the growing season. Of all the Bayer fungicides, Signature presents the most unique challenges with mixing and loading. When mixing with other fungicides it has long been the recommendation to add Signature to the tank LAST, which usually alleviates any compatibility issues among the various fungicide formulations. However, because of the vast number of products available, when mixing with fertilizers and other products, it is recommended that Aliette Signature, as well as all other fungicides is completely dissolved into solution before any fertility or other plant health products are added. Of course, a jar test is always recommended if any questions remain regarding compatibility.