Publications related to the N-Expert System:

The N-Expert software supports growers and fertilizer advisers both to calculate fertilizer demand of vegetable crops and to compile nutrient balances as required by the German Fertilizer Ordinance. A completely revised edition of the N-Expert software has now been published by IGZ. The new edition comes with an updated database on nutrient demand of all relevant field vegetable crops and nutrient demand of many other crops that are grown in crop rotations with vegetables. The program is executable on all computer operating systems.

Contact:  or  Dr. Carmen Feller (


  1. The computer program `N-Expert – Fertilizer advice and nutrient balances for field vegetables´.
    For Windows operating systems we provide an installer that installs the N-Expert program, the N-Expert database and the Java runtime environment on your computer: N-Expert – Installationsprogramm für Windows (ca. 87 MB) .
    Both the installer and the program do not require Windows administrator rights. Please note the latest information on the N-Expert software.
    Note: The default language of the N-Expert program is German. Click on “Einstellungen” – “Sprache” – “English” to change the language setting.
  2. An extensive description of the data used for the N-Expert database (the data is partly obsolete, but the description of the recommendation system is up to date): pdf (in German)
  3. A current table with Nmin target values for field vegetable cultivation: pdf
  4. A current table with nutrient offtakes of crop products and harvest residues pdf