compiled by Lee Spindler
The graceful gardenia, with its shining foliage and fragrant white flowers in spring and summer loves moist conditions and plenty of warmth. It will bloom best in areas where day temperatures are between 15–27˚C maximum range (18–21˚C is ideal) and night temperatures between 13–17˚C.
POSITION
Gardenias prefer full sun but will take light shade conditions. They are best sheltered from wind,particularly cold westerlies and salty sea breezes. An easterly or northerly aspect is ideal.
PLANTING
Gardenias like a humus-enriched, well-drained soil with a pH of 5–6, so soil is best
prepared with plenty of compost. Build up garden beds into mounds if the soil is on the heavy side and dig Searles® Water Crystals into the soil to help conserve moisture. Adding peat moss to the soil will help get young bushes off to a good start
MULCHING
Keep the root zone as protected and untouched as possible. Mulch well with organic material at a thickness of 6cm and avoid disturbing the roots. Lucerne, sugar cane or well rotted manure mulches are excellent as they will also condition the soil as they break down. Pull weeds out gently by hand. Maintain mulch levels, especially throughout a hot, dry summer.
FERTILISING
Feed each spring with a complete fertiliser. Gardenias are generally quite hardy, especially if the soil is boosted with plenty of organic compost and kept well mulched. If yours are not growing or flowering well however, it could be because the soil is too alkaline or low in nutrients. By all means, use a soil test kit if you'd like to confirm your suspicions, but there is usually no need to rigorously monitor the soil. A specially formulated fertiliser for 'acid-loving' plants such as Searles Flourish Azalea, Camellia & Gardenia will not only deliver the nutrients the plant needs, it will help maintain an appropriate level of acidity in the soil. Feed every two weeks during the flowering
season. Don’t exceed the recommended dose and don’t apply fertiliser in winter.
WATERING
Mulch the soil well to keep the roots moist but not wet. Gardenias dislike waterlogged conditions. A watering regime of three times a week in summer, once weekly in winter is recommended until plants are established. Adequate mulching can eliminate much of the need for watering.
PRUNING
Prune after flowering and tip prune in the dormant season to promote a bushier plant and plenty of flowers the following year. Spent flower heads should be removed.
PESTS AND DISEASES
Sooty mould, associated with scale, is the most common problem with gardenias. Look for the characteristic black, sooty covering on the leaves. Scale can be controlled with Searles Pest Gun and the sooty mould can be washed off the leaves. Searles Pest Gun can also help control thrips and aphids. Yellowing leaves is most likely a nutrient deficiency which can be rectified by applying Searles Flourish Azalea, Camellia & Gardenia at the recommended dose. If individual older leaves turn yellow the problem is probably magnesium deficiency, easily remedied with proprietary-brand magnesium or 2tps of Epsom Salts in a 9 litre watering can.
IN THE POT
Pot plants into Searles® Azalea and Camellia Mix and feed with Searles® Fish & Kelp
Plus at the recommended rate. Mulch the root zone well as you would plants in
garden beds and keep the pot in a full sun to part shade position.
