Like most shrubs, vitex is best planted in the spring to give it plenty of time to establish roots before winter dormancy. It is a fast-growing shrub that can shoot up as much as 7 feet in a single season, but most gardeners opt to keep this potentially invasive plant to 10 feet or less in height.

How do you keep a chaste tree small?

In winter, remove weak, twiggy growth from the center of the plant to keep it looking tidy. This is also the time to prune to encourage branching. Make cuts all the way back to a side branch whenever possible. If you must shorten rather than remove a branch, cut just above a twig or bud.

How long does a chaste tree live?

Fast growers grow old fast, too: average life span is 15 to 20 years. Being an average, that means yours might live to 40 or beyond if it is in well-drained soil and you are in a less humid part of Zone 7, 8 or 9. Mild winters, hot summers and dry air are the chaste tree trifecta.