Scouting is considered an essential component of integrated pest management strategies, but most of the techniques, which involve visual assessment, remain too time-consuming for application on a commercial scale. The global scouting method proposed here for greenhouse rose (Rosa spp.) crops combines several rapid visual methods for common pests and diseases, in a single sampling process. A 2-min observation time per sampling unit is required, with two observers. The sampling unit consists of a single stem with its flower and the corresponding basal foliage. A 90-unit regular grid (1 U/6.4 m2) was used, with weekly assessments, including a spatial distribution approach, for pest monitoring. Different grid sizes were simulated and tested with reference data, to determine whether to decrease the number of sampling units. A grid size of 1 U/21 m2 was found to be acceptable, with no significant loss of information. A more realistic and cheaper sampling strategy of this type is more likely to be accepted by growers, increasing the efficiency of crop monitoring and leading to more rational decisions.