How to Prune a Gardenia

Learning how to prune gardenias (‌Gardenia jasminoides‌) is an important part of caring for them. Gardenias grow best outdoors in USDA plant hardiness zones 7b to 11b but, in colder climates, they can be grown as potted plants and overwintered indoors. These fragrant flowering shrubs require a moderate amount of maintenance, and they must be closely monitored and cared for to ensure good blooming.

Learning how to prune gardenias takes little effort and is easy to master, but it must be done at the right time of year because pruning at the wrong time can cause fewer flowers to form.

About Gardenia Shrubs

Gardenias are known mainly for their intensely fragrant, creamy white flowers, but they also offer dark green leaves that stay on the branches year round. The number of flowers a gardenia shrub produces varies according to the cultivar and the growing conditions, but the flowers typically appear in early summer through late summer and early fall.

Gardenias are sometimes referred to as ‌gardenia trees‌ when they are pruned into a tree-like shape, ‌but they are not trees; they are small shrubs.‌ Gardenias range in height depending on the cultivar, with the dwarf cultivar Radicans (‌Gardenia jasminoides‌ 'Radicans') reaching just 6 to 18 inches in height and the taller cultivar August Beauty (‌Gardenia jasminoides‌ 'August Beauty') topping out at 6 feet.

How to Prune Gardenias

Gardenias need pruning to tidy up their appearance, to renew older shrubs with leggy growth and to change the shrub’s overall shape.

Deadheading and Grooming Gardenia Shrubs

Deadheading will improve a gardenia shrub’s appearance and help prevent seed capsules from forming, which will result in more abundant blooming the following year.

• Snip off the flower where it connects to the stem using narrow-tipped pruning shears.
• Remove the flower when the petals start to curl and discolor.
• Remove the flowers as they fade or remove them once a week.

Grooming gardenia shrubs to remove dead growth is done by snipping off the dead stem at the base where it connect to the main branches. Deadhead throughout the year as needed. Try not to snip the main branch when removing the old, dead growth.

Renewing or Cutting Back Gardenia Shrubs

Gardenia shrubs with leggy growth benefit from being cut back. The new growth will be more lush and bushy.

• Cut back two-thirds of the shrub’s new growth immediately ‌after flowering‌. Leave one-third of the new growth at the base.
• Make the pruning cuts just above a set of foliage, which will help encourage bushier new growth.
• Make the cuts at an angle so that water will run off the cuts.

Pruning Gardenias to Shape

An established gardenia bush can be pruned to create a more tree-like shape. Prune away any leaf clusters, small twigs or branching growth from the ‌lower one-third‌ of the main trunks, which will expose the trunks and lift the crown.

Prune to shape immediately in ‌early spring‌ before the gardenia plant is actively blooming.

When to Prune Gardenias

Just as important as learning how to prune gardenias is learning when. ‌Prune gardenia shrubs immediately‌ ‌after flowering‌. Gardenias form flower buds on older wood, so pruning later in the summer or early autumn will remove the new buds before they fully form, which will result in fewer flowers next year.

Deadhead to remove spent flowers as the flowers fade throughout the blooming season. In addition, remove dead or damaged branches with brown or yellow leaves as they appear throughout the growing season.

Growing and Caring for Gardenias

Pruning is only a small part of growing and caring for gardenias at home.

Environmental Conditions

‌Light:‌ Gardenias grow best in bright light. In cooler climates, they can tolerate full sun, but in warmer climates they need light shade during the hottest part of the day with direct sun in the morning.

‌Soil:‌ Moist, acidic soil is best for growing gardenias. They will not tolerate alkaline soil or very poor, sandy soil. Avoid planting gardenias near walkways because concrete alkalinizes the soil.

Caring for Gardenias

‌Watering:‌ Provide 1 inch of water each week during the growing and blooming season. Water whenever the soil feels dry. Too much and too little water can cause gardenias to drop their blossoms and buds, so careful monitoring of the soil moisture is important.

‌Fertilizing:‌ Gardenias are moderately heavy feeders. Dilute 1/4 teaspoon of 7-9-5 fertilizer in 1 gallon of water. Water with the solution each week during the growing season. Stop feeding from late summer until the following spring.