With a growing global population, maintaining sufficient agricultural production is crucial. However, agriculture faces numerous challenges today, particularly due to the undeniable impacts of climate change, which are expected to intensify pest and disease pressures. The traditional approach to combat these phytopathological issues has relied on synthetic chemical pesticides. While their use has indeed increased productivity, it is also evident their detrimental and cumulative effects on the environment, and the current negative perception of the population toward these chemicals. In response, governments are prompting the search for alternatives to synthetic pesticides, through different policies, such as the strategy From Farm to Fork in the European Union, which aims to reduce the use of chemical pesticides by 50% by 2030, among other measures. At this point, seed extracts with biocidal activity are emerging as a viable option for the control and management of various pathogenic agents, such as harmful bacteria, fungal and oomycete pathogens, and plant-parasitic nematodes. Nevertheless, it is worth mentioning that most of the studies have been only conducted under highly controlled conditions. Thus, this line of research should be still more deeply developed, including proofs under field conditions in order to become the extensive and widespread use of these bio-products a reality. In this review, we compile the main studies focused on the use of these compounds for phytosanitary purposes, describing and analysing the key metabolites, their composition, extraction processes and the mechanisms involved in their antagonistic effects. Additionally, we analyse the primary factors contributing to the limited adoption of these extracts in the field, such as the scarcity of studies under real conditions or the possible impact on non-target organisms, and discuss future prospects for their development.