A wonderful plum named after the late Geneva plum breeder, John Watson. This is a large, long, teardrop-shaped, attractive blue plum with fruits that are freestone and very high quality. Ripens with Stanley. Iroquois type. The tree is upright, spreading and somewhat willowy in growth. In taste tests this has been my favorite. Partially self-fruitful, but heavier cropping with good pollenizers such as Polly and Victory. Iroquois x Cal.4A33L; released in 1993.