To secure sufficient food volumes to feed a growing world population and at the same time taking responsibility for the environment and human health is a difficult task to solve. Pesticides have traditionally been used to ensure the food supply, but due to their lack of ability to reach their specific site of action, the amount used is often overdosed in today’s farming. One possibility to reduce the amount of pesticides severely and at the same time retain the yield would be to use adjuvants. Adjuvants are a comprehensive term for something that improves the bio efficacy of pesticides in any mechanistic way. Until recently most focus has been to increase the bio efficacy of herbicides, but lately the focus of adjuvant use have also included fungicides, which is an emerging market in agrochemical industry. The development of new adjuvants is a time consuming and costly procedure: therefore there is a need for methods that can speed up the development time. The aim of this work is to create a multivariate statistically model that can predict efficacy for non tested adjuvants and reveal the most important parameters by correlating physicochemical data for surfactants of different type with results from field trial and climate chamber experiment. The obtained models revealed that parameters affecting the retention of the droplet are the most important in field trial, while parameters affecting uptake and penetration are the most important in climate chamber experiment, indicating that the climate chamber experiment does not reflect the field trial well. The probable explanation for this difference is due to differences in the way the formulation is applied: with a plot sprayer for the field trials and an air brush in the climate chamber. In the field trial Phospholan PE105 and Ethylan 1005 had the best efficacy, and among the non tested surfactants Berol 260 and Adsee C80W were predicted to have good efficacy. In the climate chamber experiment Phospholan PE105 had the best efficacy, but the non tested surfactants Ethylan 995 and Berol 260 were predicted to have better efficacy than Phospholan PE105.