Irritant contact dermatitis (ICD) from plants is a very common phenomenon as potentially irritant plants and plant products are commonly found in the everyday environment, including the home, garden, workplace, and recreational setting. It is therefore essential to have a basic understanding of the various plant-derived physical and chemical irritants. ICD from plants is commonly divided into mechanical irritant contact dermatitis (MICD) and chemical irritant contact dermatitis (CICD). The common mechanical plant irritants include thorns, spines, glochids, trichomes, and sharp-edged leaves. Many chemical irritants have yet to be elucidated, but known culprits include calcium oxalate, protoanemonin, isothiocyanates, bromelain, diterpene esters, alkaloids, and other chemical irritants such as naphthoquinone and acids. This review details the major plant contributors to MICD and CICD, along with their respective irritants. The clinical presentations seen in ICD (versus other plant dermatoses) will also be described, along with diagnostic considerations and exposure data. We also review mechanisms for the development of ICD and current treatments for ICD from plants.