Pri določanju programa nadzorovanih poskusov je običajno treba upoštevati dejavnike, kot so podnebne razlike med pridelovalnimi območji, razlike v načinih pridelave (npr. zunanja uporaba nasproti uporabi v rastlinjaku), letne čase pridelave, vrste formulacij itd.
When establishing a supervised trial programme, normally factors such as climatic differences existing between production areas, differences in production methods (e.g. outdoor versus glasshouse uses), seasons of production, type of formulations, etc. should be taken into account.