How to treat black spots and dying leaves on Magnolia Teddy?

[leecowell]

Hi all,

I have 10 Magnolia Teddys all growing well and plenty of new foliage happening now.

Each of them however has a few dying leaves and some black spots. 

I have inspected them and see now obvious parts apart from one caterpillar and a spider I removed. I note a few spots on the stems....is this scale? I did note a couple of ants on one tree.

I have sprayed each with pest oil. Seeking any advice to keep them healthy and growing.

All has slow release ozmocote fertiliser and mulched bedding. Planted around 5 months ago.

Thanks in advance.

Lee

 

 

 

 

 

 

 

 

[MitchellMc · Accepted solution]

Hi @leecowell,

From what you’ve described and the photos, it looks like your Magnolia Teddys are generally healthy, with the new growth a great sign. The black spots on the leaves are often caused by fungal leaf spots, which can happen when leaves stay wet for long periods or there’s high humidity. The dying or yellowing of leaves down low is likely older foliage naturally dropping off, which is normal, though the black spots suggest some minor fungal activity.

The small bumps on the stems and the presence of ants could indicate scale insects. Scale is common on Magnolias and often appears as small, brown or grey bumps on stems or leaf undersides. Pest oil sprays are effective against scale when applied thoroughly, but you may need to repeat the application to target any newly hatched insects. The ants are often a sign of honeydew, a sticky substance produced by sap-sucking insects like scale, so controlling the scale will usually reduce ant activity too.

For ongoing care, keep up with your pest oil treatments, remove heavily affected leaves to reduce fungal spores, ensure good air circulation around each plant, and avoid wetting the foliage when watering. Your slow-release fertiliser and mulch are perfect for supporting healthy growth. 

Overall, your plants are doing well, and these issues are fairly common for young Magnolias and should not impact long-term health if monitored. 

Please let me know if you have any questions.

Mitchell

[leecowell]

Hi @MitchellMc,

Thanks for the response and information. Much appreciated. 

Below is a photo of affected leaves from just the last day or so. They were almost all fresh growth in the last week or two. Does this look like fungal issue? I still see no pests. 

 

This evening I have removed any affected leaves and applied a liberal spray of Yates Liquid Copper covering both sides of leaves and entire plant. Hoping this may start getting the issue under control. 

Thanks again, 

Lee

[MitchellMc]

It's quite possibly a fungal issue @leecowell. What's your watering regime like, and are you letting the soil start to dry out before watering again?

Mitchell

[leecowell]

Hi @MitchellMc,

I water twice a week, usually Tuesday and Saturday and let soil dry out. I'll check about an inch beneath the mulch for moisture content before watering. 

The yellowing leaves did have me think that but given the otherwise good health of the tree and the occurrence of black spots then rapid change once leaf has developed I'm leaning towards fungal or something similar.

Kind regards, 

Lee

[MitchellMc]

Your application of a fungal treatment certainly won't hurt the situation and hopefully will improve the health. Keep us updated.

Mitchell