Calibration books Bulbous crops

How to draw a good variety description of your bulbous crops? How to fill out the Technical Questionnaire as accurately as possible?

For the major crops for listing and/or Plant Breeders’ Rights, Naktuinbouw has developed calibration books. The calibration book serves as a very practical manual that gives an illustrated explanation of each crop characteristic mentioned in these guidelines/protocols.

How to order?

You can order the Calibration books by email.


The costs can be found in the list of fees.


Calibration books are available for the under mentioned bulbous crops. By clicking on the crop you can find the sources of information and see example pages.