Updated project metadata. Protein phosphorylation is one of the most common post-translational modifications (PTMs), which can regulate protein activity and localization, as well as protein–protein interactions in numerous cellular processes. Phosphopeptide enrichment techniques enabled plant researchers to acquire insight in phosphorylation-controlled signaling networks in various plant species. However, most phosphoproteome analyses of plant samples still involve stable isotope labeling, peptide fractionation, and demand lots of mass spectrometry (MS) time. Here, we present a simple workflow to probe, map and catalogue plant phosphoproteomes, requiring low starting materials, no labeling, no fractionation, and limited analysis time. Following optimization of the different experimental steps on Arabidopsis material, we transferred our workflow to maize, a major monocot crop, to study stress signaling upon drought.