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Optima Leaf-K is a readily available potassium foliar fertiliser. Problems with potassium uptake are often related to the pH value of the soil. A high pH inhibits potassium uptake by the roots. And in drought conditions, potassium is not released into the soil, which prevents it from being absorbed. Foliar fertilisation using Optima Leaf-K offers a solution by supplying this important nutrient to the crop.

Optima Leaf-K contains a pH-neutral, very readily available form of potassium. Crops benefit from a supplement of potassium at cold soil temperatures, during drought conditions and at the end of the growing cycle when the crop is bulking tubers, bulbs, grains and fruits. Optima Leaf-K has been specially developed to supply (arable) crops with sufficient potassium through a foliar application in periods with a high potassium demand.

Optima Leaf Range

Optima Leaf-K is part of the Optima Leaf range, a line of foliar fertilisers that are efficiently absorbed by the crop.


  • Contains a high concentration of readily available potassium.
  • Boosts the yield and size of the bulbs, tubers, grains and fruits.
  • Improves quality and storage life (brix content, firmness).
  • Increases the plant's reserves (better hardiness)
  • Does not contain any harmful nutrients such as chloride.
  • 6 x more effective than adding potassium fertilisers via the soil.
  • Better potassium uptake in dry conditions.

Nitrogen (N) as urea

29,0 g/kg

Potassium (K2O)*

238,0 g/kg

Specific gravity



6,0 - 7,0


15 - 25 mS/cm


transparent liquid

* = soluble in water



Available in 17.5 and 1000 litre containers.

EC Fertiliser

Application rates

Foliar application (maximum concentration 1:100).

Potatoes, onions:
5 litres per hectare.
Apply 3 x when the tubers or bulbs are starting to swell.

Fruit trees:
3 litres per hectare.
Apply 5 x from fruit set up to 3 weeks before picking.

Fruit trees:
If applied after picking: 5 litres per hectare.

Other crops:
5 litres per hectare.
Apply as required.

The maximum concentration for the products from the Optima Leaf range is 1 litre of product per 200 litres of spray liquid (e.g.: dissolve 1 litre Optima Leaf-Fe+ 1 litre Optima Leaf-Trace in at least 400 litres of spray liquid).

Attn: Do not exceed the total maximum dosage of 2 litres/hectare of Optima Leaf products.

Instructions for use
  • Shake or stir well before use.
  • Store frost free, indoors in a dark place. The product may crystallise at too cold temperatures (<5 °C).
  • For the best results, apply Optima Leaf-K in the early morning or late afternoon, to avoid strong sunlight. This minimises the risk of crop damage due to leaf burn. If the crop stays wet for longer, the nutrient uptake is improved.
  • Do not spray if copper hydroxide residue is present on the plant.
  • Never mix pure products together.
  • Please consult your crop consultant before combining Optima Leaf- K with other products.
  • We recommend carrying out a trial application on a small area first, before
  • applying to the entire plot.
  • This product has a shelf life of 3 years from the moment of production. The shelf life of the product is stated on the label. Opening the packaging in the meantime has no influence on this. As long as the guidelines for storage are followed the expiry date (BB) on the label is leading.
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200224 JP Optima Leaf K


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