The project “Methodology for the Accounting of Flowering Weeds in Crops Treated with Plant Protection Products” was implemented with the aim of reconciling agricultural productivity with the conservation of biodiversity, with particular emphasis on the protection of insect pollinators. Pollination is critically important for global and European agriculture, accounting for approximately 35% of crop production, while its economic value reaches hundreds of billions of euros annually. However, intensive farming, pesticide use, and the expansion of monocultures contribute to the decline of pollinator populations and the loss of habitats. The objective of the project was to develop a methodology for assessing the abundance of flowering weeds in crops treated with plant protection products (PPP), as well as to determine their importance for pollinators and establish practical accounting principles. The project involved the analysis of scientific literature, field observations, and data analysis in various agricultural crops (oilseed rape, cereals, potatoes, sugar beet, maize, hemp, and orchards). The research showed that weeds, although traditionally considered undesirable plants, perform an important ecological function by providing pollinators with nectar and pollen, especially during periods when agricultural crops are not flowering. Weeds increase pollen diversity and help avoid “food gaps,” thereby contributing to the survival of bees and other insects and to the stability of agroecosystems. It was also found that with intensive herbicide use, the presence of flowering weeds in crops is generally low (usually up to 1–5% of projective cover). However, if weed control is inadequate, their abundance can increase significantly. The distribution and importance of weeds vary among different crops: for example, in oilseed rape and cereal crops they may serve as an important additional food source for pollinators, while in hemp or maize crops they are usually only sporadic. The main output of the project is a standardized methodology for the accounting of flowering weeds. It defines: the principles for evaluating flowering weeds (number of flowers and ground cover); the locations of assessment (field edges and field interior) and their number depending on field size; the timing of assessments for different crops according to growth stages (BBCH scale); the allowable threshold – up to 10% projective cover of flowers; cases where assessment is not required (e.g., weeds rarely visited by pollinators or during oilseed rape flowering). In addition, the project proposed amendments to the Integrated Pest Management guidelines, stipulating that when a higher abundance of flowering weeds is present, plant protection products should not be applied during pollinator foraging periods. This contributes to practical farming decisions oriented toward ecological sustainability and compliance with regulatory requirements. In summary, the project developed a research-based tool for the objective assessment of the occurrence of flowering weeds and their impact on pollinators. The methodology can be applied both in farming practice and in the work of supervisory authorities, helping to balance effective weed control with the conservation of biodiversity and the protection of pollinators.