Osmocote Exact High K 12-8-19

Osmocote® Exact High K 3-4M (12-8-19+1.8MgO+TE) is highly suitable for pot plants requiring high-potassium feeding over 3 to 4 months and where compact growth is important. Also ideal for herbaceous perennials and for use in nitrogen-rich irrigation water. Osmocote® Exact High K works very well in combination with Peters® Professional water-soluble feeding. The recommended rates should be adapted, depending on the amount of water-soluble feeding. Can be used in combination with Osmocote® CalMag when an addition of calcium and magnesium is recommended (for example soft water cultures) or in cultures that demand more nitrogen during the first months of growth. For crops with high iron demand, this product can be combined with Osmocote® Iron.


  • Nutrients released over 3 to 4 months
  • Highest efficiency in release during the cultivation period
  • Highest consistency, as every batch of product is identical
  • Highest safety for plants


        Composition: 12-8-19+1.8MgO+TE

        Application rates

        Recommended application rates for pot plants: 2-3g/l up to 2.5-4g/l

        ATTENTION! Add a maximum 0.5 g/l NPK starter fertilizer in combination with Osmocote® Exact High K. Attention The recommended rates above are based on unfertilized substrates. These are general recommendations. Adjust for specific situations, such as use in tunnels or greenhouses, or specific climate conditions. Trial first on a small scale before changing the rate, application or any other variables. 

        How to use:

        1. The longevity of Osmocote High K is determined at 21ºC. At lower average soil temperatures the product will work longer, at higher average soil temperatures shorter. Indicational: 16ºC: 5-7M, 21ºC: 5-6M, 26ºC: 4-5M.
        2. Partly used bags must be closed/sealed properly.
        3. Store under dry conditions.

        Sale price€4,80
        Size: 300 g