How to treat Gardenia with yellow leaves and black spot?

TD2

I purchased a gardenia plant from Bunning 1 month ago. Recently, my plant has been having yellow leave with black spot. I put the plant on a spot with morning sun, water every afternoon, cut all the yellow leave and spray eith Brunning Bug and Fungus kill 2 time, each 1 week apart. The problem is still there. The plan also has no flower anymore. Buds fall before even opening.

What should I do? 

MitchellMc

Welcome to the Bunnings Workshop community @TD2. It's brilliant to have you join us, and many thanks for your question about Gardenia care.

Yellowing leaves with black spotting, buds dropping before they open and a general lack of new growth often happen when the mix is staying too wet for too long. Gardenias like consistent moisture, but they dislike having their roots sitting in damp, heavy soil.

How long does the potting mix stay damp after each watering? Some store-bought mixes can hold more water than expected, and daily watering can mean the root zone never gets a chance to breathe. Does the pot drain freely after watering, or does excess water pool in the saucer? Any lingering moisture can create the exact stress that leads to yellow leaves and bud drop. Only water when the top 5cm of soil starts to dry out.

The occasional yellow leaf is normal, but continued spotting after fungicide suggests the roots are a little unhappy. So I would adjust your watering regime if needed.

Here's a helpful guide: How to grow and care for Gardenias.

Please let me know if you have any questions.

Mitchell