The biodiversity of geophytes is higher in Greater Cape Floristic Region (GCFR) of South Africa than anywhere else in the world. The GCFR is a winter rainfall region where geophytes survive hot and dry summers as below-ground tubers. Winter rainfall is predicted to become less consistent due to climate change which will impact survival of some geophyte species. To study the effects of drought during the growing season, three geophytic species of Pelargonium (sect. Hoarea) were subjected to an acute dry-down experiment.  Leaf tissue was collected from control and treatment plants. Differentially expressed genes (DEGs) were identified using a computational pipeline including Trimmomatic, Trinity, EnTAP, GO annotation with g:profiler, and Gfold and R package-DESeq2. In all species, most enriched drought-responsive genes were related to protein processing in the endoplasmic reticulum, plant hormone signal transduction, response to abiotic stimulus, and response to stress. Differentially expressed genes in P. oblongatum were primarily associated with aging, plant organ senescence, and leaf senescence. Interestingly, this species had the largest leaves and was the only species to show plastic reduction in leaf size under drought stress. On the other hand, P. auritum had the smallest leaves out of all three species and an earlier study showed that it was physiologically the most resilient to drought. Drought-responsive genes in P. auritum were implicated in signal transduction, ion homeostasis, and Abscisic acid (ABA) signaling. In contrast, in P. incrassatum, major enriched genes categories involve plastids, thylakoids, and chloroplast stroma, implying that drought in this species affects photosynthetic machinery. Despite their common growth form, each species responds uniquely to drought in terms of gene regulation and physiology.