Bugs, caterpillars or ?? eating my magnolia leaves

twopenny

So 2 years now my potted Magnolia has been defoliated. Now it's getting so it isn't recovering.

I've just taken it out of the pot and found snails, woodlice and at the last minute on the old compost some black bugs that had abdomen, thorax and head and scuttled slowly.They aren't any of the usual beetles

I've been researching and don't think it's vine weevil as these were shiny and the roots are fine  and healthy but I've not seen the like before and I'm countrywise. Can't find the like online.

Or could be caterpillars but I'd looked for those many times with no sucess.

I've repotted with half new compost (don't have more new stuff) and reluctantly half the old. Put cinnamon sticks chopped up in the compost, a length of pipe to ensure water goes mid pot and watered throughly with Phostrogen in it. I'm making a cinnamon spray too to wash the branches in case that helps.

Any ideas what it could be? The leaves have been nibbled a bit, they have been curled with almost a web but nothing inside. Eventually they all go brown and die off.

All thoughts appreciated.

[Deleted User]

I encounter similar with some of my potted shrubs and i'm sure it's the snails, one of the buddliea's was the worst affected, i decided to take it out of the pot, put it in the ground and it's now growing properly, no eaten leaves at all.
These things are an absolute menace 🤬

Apodemus

I've no experience of growing magnolias, but always assumed that they needed planty of root space - is it possible that yours is simply not a variety that enjoys being constrained?

twopenny

Thank you both. This is more devastating than snails though they may have had their part to play. There is this slight web thing but no sign of insects not even in nearby cobwebs.

It's so far not affected any other plant in pots or otherwise.

I'd love to have all my potted plants in the ground but on a slope made of builders rubble and water pipes one side and electrics from street lamp to my house the other.

Money_Grabber13579

I had 3 magnolias in pots and they all suffered the same fate. Leaves chewed and eventually they just dropped off and died. They recovered once but it then happened again and it proved to be the end of the plants.

twopenny

Well it's good not to think it's just me - but not cheered me up any.

I'll try the cinnamon now and in spring. Maybe put the pot away from the wall into the howling gale and rain in the hope of detering bugs.

It has rained a bit a couple of nights so I'll do a depth check on the soil at the front with a poker. See if there's anywhere diggable but I think the ground is too dry there for it.