Troubleshooting
Magnolia 'Susan' problems — and how to fix them
Magnolia 'Susan' (Magnolia 'Susan') is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Sparse flowering in shade
Too little light reduces the number of blooms. Site in full sun or only light shade to maximise the flower display.
Chlorosis on alkaline soil
Yellow leaves with green veins on chalky ground indicate iron lock-out. Mulch with leaf mould, apply sequestered iron, or grow in ericaceous compost in a container.
Root disturbance stress
Brittle fleshy roots resent digging and transplanting, leading to dieback. Plant carefully, mulch rather than cultivate around the base, and minimise disturbance.
Scale insects and sooty mould
Magnolia scale produces honeydew that supports black sooty mould on stems and leaves. Treat scale infestations and wipe or wash affected growth.
Prevent magnolia 'susan' problems before they start
Most magnolia 'susan' issues are care-mismatch, not bad luck. Dial in the basics:
Looking for magnolia 'susan' in general rather than its problems? Read the full magnolia 'susan' care guide — light, water, soil and feeding.
Magnolia 'Susan' problems — FAQ
Why is my magnolia 'susan' sparse flowering in shade?
Too little light reduces the number of blooms. Site in full sun or only light shade to maximise the flower display.
Why is my magnolia 'susan' chlorosis on alkaline soil?
Yellow leaves with green veins on chalky ground indicate iron lock-out. Mulch with leaf mould, apply sequestered iron, or grow in ericaceous compost in a container.
Why is my magnolia 'susan' root disturbance stress?
Brittle fleshy roots resent digging and transplanting, leading to dieback. Plant carefully, mulch rather than cultivate around the base, and minimise disturbance.
Why is my magnolia 'susan' scale insects and sooty mould?
Magnolia scale produces honeydew that supports black sooty mould on stems and leaves. Treat scale infestations and wipe or wash affected growth.