Hormones in tomato leaf development

•Leaf development is a model for plant developmental flexibility.•Tomato leaves are compound and show a wide variability of size and form.•Auxin, Gibberellin and cytokinin interact to pattern tomato compound leaves.

Leaf development serves as a model for plant developmental flexibility. Flexible balancing of morphogenesis and differentiation during leaf development results in a large diversity of leaf forms, both between different species and within the same species. This diversity is particularly evident in compound leaves. Hormones are prominent regulators of leaf development. Here we discuss some of the roles of plant hormones and the cross-talk between different hormones in tomato compound-leaf development.