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Optima Leaf-K is a direct 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 organically complexed foliar fertilisers that are very efficiently absorbed by the crop.


  • Contains a high concentration of directly available potassium.
  • Boosts the yield and size of bulbs, tubers, grains and fruits.
  • Improves quality and storage life (brix content, firmness).
  • Increases the plant's reserves (better hardiness).
  • Better potassium absorption in dry conditions.
  • Improves the drought resistance of the crop.
  • Much more effective than adding potassium fertilisers via the soil.
  • Very low chloride content.

Nitrogen (N) as urea

44 g/L

Potassium (K2O)*

350 g/L

Specific gravity

1,48 kg/L


7,0 - 8,0


35 - 50 mS/cm


transparent liquid

* = soluble in water

Low in chloride



Available in 17½, 300 and 1000 litre containers.

CE Fertiliser

Application rates

Foliar application (maximum concentration 1:50).

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.

2-3 litres per hectare
1-2 Applications per year around flowering / before harvest.

Grain crops:
2-3 litres per hectare
1-2 Applications per year around flowering / before harvest.

Peas and beans:
2-3 litres per hectare
1-2 Applications per year around flowering / before harvest.

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

Instructions for use
  • Shake or stir well before use.
  • Store in a cool dry place away from direct sunlight. This product has been tested and can be stored safely at temperatures from 5°C to 25°C. Crystallisation and/or sedimentation may occur below 5°C.
  • Apply under suitable spraying conditions (e.g. temperature, humidity, wind speed). Do not treat if the temperature is >25°C or if it might rise to >25°C in the hours after application. Preferably perform the treatment at the end of the day. Do not apply product close to harvesting.
  • Do not spray if copper hydroxide residue is present on the plant.
  • Never mix pure products together.
  • We recommend carrying out a trial application on a small area first, before applying to the entire plot.
  • The shelf life of the product is stated on the label. As long as the guidelines for storage are followed the expiry date (BB) on the label is guaranteed.
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210114 JP Optima Leaf K jcn


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