Potassium fertilization of rapeseed

Rapeseed is a basic oil plant in Poland and Europe. Winter rape with a yield of 3.5 t of seeds with the appropriate weight of straw uptakes 80 kg P2O5, 186 kg N and almost the same amount of potassium (180 kg K2O). In autumn, rapeseed plants absorb up to 25% of the potassium accumulated during the vegetation period. Plants well nourished with potassium develop a stronger root system in autumn and a thicker root.

Potassium has a positive effect on the plants condition during winter period, which significantly reduces wintering losses. Potassium also increases the resistance of plants to spring frosts, often occurring in May. This element takes part in the control of water management. It also participates in opening and closing crevices. Thanks to this, plants well supplied with potassium do better during periods of rainfall deficiency.

This component determines the use of nitrogen, so plants malnourished with potassium have problems with taking up this element, which limits the development of the assimilation surface of the plant, and this causes lower yields of dry matter of individual plant parts.

Potassium also takes part in the transformation and transport of assimilates. It has a positive effect on the formation of ATP - an energy carrier. It also stimulates the process of fat formation, and an increase of its content in seeds. It participates in protein accumulation. If there is not enough potassium nutrition, the protein content decreases regardless of the level of supply of nitrogen to plants. Plants well supplied with potassium are also more resistant to fungal diseases and pest infestation. Potassium also limits the lodging of plants. It also increases nectar secretion, which attracts rapeseed pollinating insects and contributes to abundant pods formation.

Recommendations for fertilizing rape with potassium:
The amount of potassium doses depends on the quality of the soil and its abundance in the available form of this nutrient as well as the expected grain yield and amounts to 50-180 kg K2O/ha in worse soil conditions and 60-180 kg K2O/ha on better soils. If manure is used under rape, potassium and phosphorus doses can be reduced by 25-30%.

Doses of phosphorus and potassium for winter rape, kg/ha (Wałkowski 2005)



Zasobność gleby

Soil suitability complex

Wheat very good

Wheat good

Rye very good

Strong cereal-fodder

Mountain wheat

Wheat not suitable

Rye good








Very low




























Very high







Expected yield, t/ha

above 3,5

2,5 – 3,5

below 2,5

Rapeseed is a chlorine-neutral plant, so for its application a high concentration potassium salt should be used. It is best to apply the whole dose of potassium salt during sowing. Only in lighter soils, where there is a risk of leaching and large losses of potassium, 2/3 of the dose is applied in autumn and the remaining 1/3 in spring. Similarly, if for any reason potassium fertilization was not performed before rape sowing, it should be performed as early as possible in spring.

When determining the potassium dose, more attention should be paid to improving the soil's abundance in available potassium than to the amount of pre-sowing fertilization with this nutrient. The aim should be to ensure that the available potassium content of the soil is at least medium.

Written by dr inż. Arkadiusz Artyszak

We kindly inform you that the website uses cookies. To learn more about how we use cookies and how to change your cookie settings if you don't want them to be stored on your computer, please refer to our Cookies Policy of our website AUREPIO-KALIJ.PL . By continuing to use this site, you consent to our use of cookies according to your browser settings.

At the same time, we would like to inform you that as of 25 May 2018, Regulation (EU) 2016/679 of the European Parliament and of the Council of 27 April 2016 on the processing of personal data (GDRP) is in force, the information clause is available here
The Policy of personal data processing at www.aurepio-kalij.pl with reference to the Regulation (EU) 2016/679 of the European Parliament and of the Council (EU) 2016/679 (GDPR).
1. Whose data do we process?

We process the data of the following persons:

  • Persons employed in or representing entities that are business partners of Aurepio-Kalij Sp. z o.o. ;
  • Employees of Aurepio-Kalij Sp. z o.o.;
  • Other stakeholders in any way connected with Aurepio-Kalij Sp. z o.o.;
  • Users of the AUREPIO-Kalij.PL website (hereinafter referred to as the Website) who used the Contact Form and provided their personal data.

2. What data do we process?

  • Name and surname, company, business address, correspondence address;
  • Numbers in certain official registers (e.g. NIP, REGON, PESEL, etc.);
  • Contact details - e.g. e-mail address, telephone number;
  • Position or functions performed by you within your organisation;
  • Other data such as: bank account number, education, professional title, etc;
  • Your data collected from publicly available sources, such as CEIDG and KRS registers.

3. Who is the aministrator of your personal data?
The administrator of your personal data is Aurepio-Kalij Sp. z o.o. with its registered office in Warsaw, Aleja Jana Pawła II nr 11, 00-828 Warsaw, registered under KRS number: 0000354503, NIP number: 527-26-26-360, REGON number: 142296306.
4. Security of your personal data

In order to ensure the security of personal data entrusted to us, we have developed internal procedures and recommendations to prevent the disclosure of data to unauthorized persons. We control their implementation and constantly check their compliance with the relevant legal acts - Regulation (EU) 2016/679 of the European Parliament and of the Council of 27 April 2016 on the protection of individuals with regard to the processing of personal data and on the free movement of such data and repealing Directive 95/46/EC (general data protection regulation), the Act on personal data protection, the Act on the provision of electronic services, as well as all kinds of implementing acts to the laws and acts of the EC Community law and guidelines of the European Data Protection Board.

Only authorized employees of Aurepio-Kalij Sp. z o.o. and persons dealing with the Service have direct access to personal data of Service users. Authorized persons are obliged to keep this data in strict confidence and prevent access to them by unauthorized entities.

5. To whom can we pass on your personal data?

Your personal data will not be passed on to other entities except for the following:

  • The data may be transferred to Aurepio Sp. z o.o. for processing;
  • The data may be entrusted for processing to suppliers of IT services provided to Aurepio-Kalij Sp. z o.o.;
  • Data may be transferred to public administration authorities at their request in accordance with applicable law.

6. For what purpose and on what basis do we process your personal data?

We process your personal data for the following purposes:

  • if necessary for the fulfilment of contractual obligations of the Company towards you or for the fulfilment of activities prior to the conclusion of the contract with you;
  • if essential for the fulfilment of our legal obligations or those expressly prescribed by law;
  • if necessary for the performance of the legally justified interests of the Company (art. 6 sec. 1 letter f) GDPR), such as: enabling the Company's representatives to contact you, preventing criminal activity, verification of clients in public registers, marketing and analytical purposes;
  • Handling of messages sent to us via the contact form - each time with consent to the processing of personal data (pursuant to Article 6(1)(a) of the GDPR);

7. What rights do you have over your personal data?

You have a right to:

  • Requests for access to your personal data;
  • Requests for rectification of your personal data;
  • Request for deletion of your personal data or limitation of their processing;
  • Object to the processing of your personal data;
  • Request to restrict the processing of your personal data;
  • Request the transfer of your personal data;
  • You may also withdraw your consent to the processing of your personal data, which will not affect the lawfulness of the processing of your personal data by Aurepio-Kalij Sp. z o.o., which was carried out on the basis of consent prior to its withdrawal.

If you believe that we are processing your personal data in violation of the law, you have the right to lodge a complaint with the supervisory authority - the President of the Office for Personal Data Protection.

8. How long will we process your personal data?

Your personal data will be stored for as long as Aurepio-Kalij Sp. z o.o. needs it for the purposes for which it was collected. Personal data will be stored until any of the following situations occur:

  • until the withdrawal of consent to their processing,
  • until the Administrator declares them out of date,
  • until it expires
  • until meeting the purpose for which they were collected,
  • until expiration of any claims from the persons that the data refers to.
9. More information?
We are committed to ensure that the personal data entrusted to us by you is secure and stored in accordance with the law and high standards of data protection. If you would like more information about how we protect your personal data, please read our Cookies Policy.