How to treat Frangipani plant mould?

beexdee

Hi team, I was gifted a young potted frangipani plant recently and with the cold Sydney weather (and some other garden pests) I didn’t want to leave her outside so I kept her in our living room expecting it wouldn’t be too extreme in temperature. 
fast forward 2 weeks only and she has already developed some mold or mildew or fungus I think?? And it’s quite noticeable. I think even the leaves are showing some distress. 

what product could I get to address this issue?

Thank you! 

EricL

Hello @beexdee 

Your young frangipani is definitely showing signs of stress, likely due to a combination of cold shock, excess moisture, and lack of airflow from being kept indoors. The yellowing leaves with dark spots are classic signs of fungal leaf spot, often triggered by cool temperatures and high humidity. The fuzzy white growth on the soil is saprophytic fungi, which feed on decaying organic matter. While they’re not directly harmful to the plant, their presence signals that the potting mix is staying too wet, which can lead to root rot or attract pests like fungus gnats.

To help your frangipani recover, start by moving it to a brighter, more ventilated area. A spot under cover outdoors, such as a verandah or near a north-facing window, is ideal during Sydney’s cooler months. These plants are deciduous, so it's normal for them to lose some leaves and go into dormancy in winter. Don’t worry too much if it looks sparse for now.

Next, allow the soil to dry out completely before watering again. Remove the top 2–3 cm of the potting mix where the mould is visible, and replace it with dry, fresh premium potting mix such as Osmocote Indoor. This will help reduce fungal activity on the soil surface.

For treatment, head to Bunnings and pick up a fungicide like Yates Anti Rot or Eco-fungicide if you prefer an organic option. Spray both sides of the leaves thoroughly, and repeat after 7–10 days if needed. If you’d like to treat the soil too, lightly dust the surface with Richgro Fungicide Dust or use the Eco-fungicide as a diluted soil drench just once.

In the long run, consider repotting your frangipani in spring into a well-draining mix like cactus or succulent soil, or amend your current potting mix with coarse sand and perlite. Frangipanis don’t like soggy roots, so better drainage is key.

Please remember to wear personal protection such as gloves, goggles and a mask when using chemical sprays.

If you need further assistance, please let us know.

Eric