Embodiments described herein relate generally to plant extract compositions and methods to isolate cutin-derived monomers, oligomers, and mixtures thereof for application in agricultural coating formulations, and in particular, to methods of preparing plant extract compositions that include functionalized and non-functionalized fatty acids and fatty esters (as well as their oligomers and mixtures thereof), which are substantially free from accompanying plant-derived compounds (e.g., proteins, polysaccharides, phenols, lignans, aromatic acids, terpenoids, flavonoids, carotenoids, alkaloids, alcohols, alkanes, and aldehydes) and can be used in agricultural coating formulations.