I bought these 2 port wine magnolias from Bunnings at the start of Summer 2025. They are in large pots with high quality potting mix and mulch. I have also given them Seasol about 3 times. I have noticed that some leaves are going brown and dropping, especially in the lower section. I watered them every 2-3 days over summer as they're in black pots, get afternoon sun and were new. Has anyone got any ideas as to why this might be happening? Would love any help!! Thanks
Hello @Tam W
Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your Port wine magnolia.
It looks like your Port Wine Magnolia is generally healthy overall, but showing some fairly common stress signs that often come up with newly planted specimens in pots. The browning and dropping leaves, particularly on the lower section, are usually linked to a combination of adjustment stress and moisture balance rather than anything too serious.
Because they’re in black pots with afternoon sun, the root zone can heat up quite a bit, which speeds up drying but can also stress the roots. Watering every 2–3 days over summer sounds reasonable, but in this situation, it can sometimes lead to a cycle of the mix drying out on top while staying a bit too damp deeper down, especially in larger pots. That can cause older leaves to yellow, brown, and drop as the plant sheds what it can’t support. It’s also very normal for magnolias to drop some older inner foliage as they settle in after planting.
The good news is you’re already doing a lot right. Seasol is excellent for reducing transplant stress, so continuing that every few weeks is a good idea. What I’d suggest is just refining the watering slightly by checking moisture a few centimetres down in the mix before watering again, rather than sticking to a fixed schedule. You’re aiming for consistently moist, not wet soil. If the pots don’t drain freely, it’s worth double-checking that as well.
A light application of a slow-release fertiliser like Osmocote Native or Controlled Release (both available at Bunnings) can also help support steady growth without pushing the plant too hard. Try to keep the pots slightly shaded on the sides if possible, even just by grouping plants or using a lighter-coloured outer pot, to reduce heat stress on the roots.
Overall, this looks like a normal settling-in phase rather than a major problem. As the weather cools and the roots establish further, you should see more consistent, healthy growth and less leaf drop.
Here is a handy guide: Growing, Pruning & Caring for Magnolia
If you need further assistance, please let us know.
Eric
