My magnolia leaves are suddenly turning yellow. I live in a suburb of Perth. I was recently away for 10 days but it rained the whole time I was away. I've been back now 10 days and have watered it once.
Hi @Bectacular,
Welcome to the Bunnings Workshop community, it is wonderful to have you with us.
Yellowing magnolia leaves without evidence of attack from things like bugs can sometimes be a bit of a stress response to changing weather conditions.
Given you had consistent rain while you were away, the soil may have stayed quite wet for an extended period. Magnolias don’t love sitting in overly wet soil, so some yellowing can be a sign of stress from too much moisture rather than too little.
Seasonal changes can also play a part. A sudden cold snap or shift in temperatures, can stress the plant and trigger some leaf yellowing, particularly on older leaves. It is fairly common as we move through seasonal transitions to see plants reacting out of stress.
At this time, I think the best course of action is to check the soil for moisture as I suspect this is the major factor.
If you scrape back the debris from around the base of the tree and stick your finger into the soil, around 5-10cm, is the soil damp? When you watered the tree did you happen to notice how quickly the soil drained?
If the soil is still damp, I would ease off watering for now and let it dry out a bit. It may also be worth tidying up around the base of the tree so you can clearly check how well it is draining and ensure nothing is trapping excess moisture. Going forward, aim for a deep but less frequent watering rather than light top ups.
You can also look at improving the soil and its drainage capabilities by gently aerating with a garden fork, being careful not to damage the roots and mixing in some compost to add nutrients and promote beneficial insects which help create channels in the soil that help with drainage.
You might also like to have a read through https://www.bunnings.com.au/diy-advice/garden/planting-and-growing/growing-pruning-and-caring-for-magnolia-trees-magnolieae for some general guidance.
Hopefully it is just a temporary response, and it should bounce back pretty quickly.
Jacob
