The plant hormone abscisic acid (ABA) plays a central role in adaptive responses to abiotic stresses that adversely affect crop growth and productivity. However, ABA photoinstability limits its use in agriculture. To overcome this drawback, in this study, we developed photostable ABA analogues, the (+)-BP2A compound series (compounds -), in which the dienoic acid side chain of ABA was replaced with phenylacetic acid.