Gardenias are a popular warm-climate shrub, valued for the beauty of the pure white blooms, as well as for the sweet fragrance. Deadheading, which is the process of removing wilted or spent gardenia blooms, will not only improve the appearance of the gardenia bush, but will prevent the bush from going to seed. Instead, the plant's energy will be used to continue producing beautiful gardenia blooms as long as possible.
Sanitize the blades of a pair of sharp garden shears before deadheading the gardenia blooms. Wipe the blades with rubbing alcohol or a mixture of ten parts water and one part bleach. Always use a clean blade so that bacteria won't be passed to the plant.
Inspect the gardenia bush often, and deadhead the gardenia blooms when they begin to wither or turn brown. Hold the gardenia branch with one hand, and with the garden shears in your other hand, make a diagonal cut at a leaf, or where the stem joins to a larger stem. Be careful not to remove buds that may be forming lower on the stem.
Pick up any spent blooms that fall to the ground under the gardenia bush, as a build-up of debris will invite disease and pests. Rake up the spent blooms and other debris, and dispose of the debris, or toss it on the compost heap.