Botanical name
Gardenia augusta
Common name
Common Gardenia, Cape Jasmine
Gardenia plant description
Widely used throughout warm Australian gardens, you won’t have to walk far to find a species of Gardenia in your neighbourhood. Whilst there are over 200 species of Gardenia, arguably the most popular and commonly found is Gardenia augusta.
Evergreen shrubs from southern China, the Common Gardenia has attractive, glossy deep green foliage and highly fragrant white flowers that fade to cream. Flowers appear over a few months from mid Spring.
The best known Gardenia augusta is ‘Florida’ which is a shrub that grows to 1m x 1m with lovely white flowers about 7cm wide. There are many other popular cultivars available including ‘Radicans’, a prostrate, ground cover Gardenia with significantly smaller flowers and leaves and ‘Magnifica’ which is a larger variety with generally fewer flowers.
Climate
Warm temperate, sub-tropical, tropical
Plant cultivation and care
Gardenias require well drained, nutrient rich, neutral to acid soil. Sometimes touted as being suitable for full sun, the glossy leaves burn quite easily in Summer, resulting in a less than healthy looking plant. A position in light shade is definitely the best position. Plenty of water during the warmer months (not enough can cause flower buds to drop off) and regular fertiliser application is also key.
Gardenias prefer warm, humid climates. Avoid frost.
Plant use
Fragrant gardens, shrubberies, borders
Pruning
Gardenias do not need much in the way of pruning. Tip pruning after flowering will promote bushier growth. Remove dead flower heads as they appear as well as any dead or scraggly branches if present.
Pests and diseases
Plants that do not grow and tend to wilt very quickly can be the result of Root Rot Nematode. Pale green or yellowing leaves can be caused by an Iron or Magnesium deficiency although the occasional yellow leaf is quite normal. Flowers with tiny moving black specks are probably Thrips. Mealybugs, White Wax Scale and Soft Brown Scale commonly attack Gardenias as well.