How to treat Gardenia with leaves turning black?

3jidaddy

Hi. My first time growing gardenias and I found issues.

1. I see that some flower buds were cut off before blooming. 

2. Some leaves are turning black.

3. Some with insects even though I have been applying eco oil weekly.

Appreciate me if you could give me some advices. Thank you. 

JacobZ

Hi @3jidaddy,

Growing gardenias for the first time can be challenging, but addressing these issues is manageable with some care.

The flower buds likely dropped prematurely due to environmental stress like inconsistent watering, temperature changes, or insufficient nutrients. Ensure the soil is moist but not waterlogged, maintain consistent watering, and use a fertilizer such as Scotts Osmocote Roses, Gardenias, Azaleas And Camellias Controlled Release Fertiliser to support bud development.

The black leaves may result from fungal diseases like sooty mould or overwatering. Check for pests like aphids that secrete honeydew, as this can lead to mould. Remove affected leaves, improve air circulation around the plant, and water only the soil to avoid wetting leaves.

If insects persist despite using eco-oil, ensure you're applying it correctly, covering both the tops and undersides of leaves and physically remove any eggs or insects like those I have circled below. 

Keep the plant healthy overall, as strong gardenias are more resistant to pests and diseases.

Allow me to tag @mich1972 and @Noelle for their thoughts.

Thank you for your questions and if you have any more, please don't hesitate to ask.

Jacob