Gardenia shrubs are prized for their deep green foliage and aromatic white flowers. An evergreen, gardenias are more common in the warm areas with mild winters. Planted as hedges or in borders, a gardenia plant requires regular pruning to maintain its shape and size so it continues to fit into your landscaping. Gardenias don't require frequent pruning; every other year is enough for most shrubs, and you may be able to go as long as three years between pruning.
Wait until the gardenia shrub is finished flowering for the season. For most varieties, this is in late May to early June, though there are late-blooming varieties that will bloom through mid-summer.
Prune immediately after blooming until late summer, as buds will set in early autumn for the following year. Use sharp pruning shears so as not to damage the wood on the shrub.
Cut the outer branches to the desired length. Cutting each branch to the same length helps define the shape of the shrub.
Trim any inner branches that extend out farther than the newly pruned outer branches. Cut both old wood and fresh green wood, as gardenias set buds on both old and new growth.
Clean the pruning shears in a solution of soapy water, rinse and dry thoroughly after pruning each bush. This prevents any disease from being carried from shrub to shrub by your pruners. Clean a final time before storing the pruners after you are done.