Chaste tree (Vitex agnus-castus) is a deciduous shrub that bears clusters of purple flowers in the summer. Left unpruned, it can become a sprawling, vase-shaped shrub that grows to 20 feet tall with an equally wide spread. It is sometimes trained as a single-trunk small tree.The leaves of the chaste tree are very reminiscent of the marijuana plant (Cannabis sativa), with five leaflets in a palm-shaped arrangement. The leaves have a fragrance similar to that of the herb sage. The purple flower clusters (called panicles) look like those of the butterfly bush (Buddleja spp.) Varieties with white flowers are also available. The black fruit contains four seeds that look like peppercorns and are sometimes used to flavor food.