Diseased Magnolia and Oak leaves
marksmith2 Posts: 2
does anyone know what is causing the magnolia leaves to end up like this. Similar problem with oak trees too. All plants are in pots. Only happened this year.
any help greatly appreciated
The good thing is, they're still green. Probably insect/slug and snail damage when the leaves were in bud and the dieback is just damaged tissue. I don't doubt they'll all be fine next year. That said, any plants in pots, especially larger subjects, are likely to show greater reaction to physical damage because they have to fight for nutrients and water in containers, be it because of irregular supply or dry spells.
I think that's scale insect damage. I've seen more and more of it in recent years. The RHS doesn't list it as a problem for magnolia but they're about. Have a look under the leaves. You can spray again them.
thanks for the replies.. checked under leaves can't see anything. Just checked and it's affected my grey alder too! Nothing to see insect wise
A couple of my magnolia in pots look similar and I think it's due to the pots getting a bit too dry earlier in the year. The same varieties I have planted in the ground look fine. If you need to keep them in pots, I would put them into larger ones and use a John Innes #3 mixed with about 20% of ericaceous compost (and leaf mould if you are lucky enough to have any) as this seems to hold water well.
Last edited: 02 October 2016 17:25:17