Japanese maples and the hot weather

[Yamadori]

Hi all, if you have a Japanese maple in a pot in your garden and are able to move it into the shade for a few days, then it will thank you. It will also really help if you can stand the pot in water - deep saucer, washing-up bowl, whatever.

As well as preventing the soil from drying out, the water will increase humidity around the plant.

This applies particularly to acers, but most other plants in pots will benefit too.

I've repurposed some growbag trays and the acers are now well-watered and safely tucked into a shady corner

The branches of my acer turn black in different areas. I cut them off. It’s not as bad since I planted it in a north facing spot. Is this wind burn?

Just wanted to say thank you OP - think you've saved a couple here!

What time of year do the branches go black, and do you know what variety it is? Some are far less robust than others. Do they go black from the tips backwards, or from the middle of a branch, or from where they join a main branch or the trunk? Roughly whereabouts in the country are you, and what sort of soil type do you have?

From the tips backwards. I sprayed with a fungal concoction I got in the garden centre but it didn’t do very much so I thought maybe it was where it was positioned.

so I googled and it said to place it facing north. It has improved quite a bit, definitely less black stems.

Funny you mention time of year, it has improved with the better weather, it was definitely worse in winter and spring. We have a large windy garden with not much shelter, I’m working on this, it’s a new garden/house, I suspect our soil is a bit crap, I think the builder removed all the good top soil. Thanks for your reply!

@TheBigPeach You are doing the right thing, it does sound like it is probably a fungal infection, possibly brought on by being too wet in the winter. The Roseclear fungicide is a good one. Keep pruning off the dead bits back to healthy wood, and seal the cut ends with vaseline (I kid you not!). Try to clear away any fallen leaves etc from around the base of it, otherwise they can harbour the nasties from year to year. Don't compost anything from it, chuck it in the bin. It is also a good plan to feed the tree well, as a healthy tree can fight off disease better.

With the help of two other people I have managed to get mine under the garden shelter so they will be in shade all day, have given them a good water too. The light leaved one looks lovely and healthy but on the dark leaved one about 50% of the leaves have dried and curled. Hope I wasn’t too late, the remaining 50% still look ok.

Losing leaves isn't too much of a problem, they can grow another set. Losing the fine roots is more of an issue, because those are what the plant uses to drink.

Thanks yamadori, hopefully the shade and the water prevent that.

Thanks so much 😃

I'm on a big (worldwide) gardening forum,and folk don't seem to realise Acer's are Japanese woodland plants. My back garden is north facing, but because it's a detached bungalow,sun comes over the roof,my pale leaved Acer's are under various trees...in pots,I have a red one in the ground,semi shaded. I found the ones who suffered wind or sunburn in the past, didn't recover. Mine are big pots, mostly plastic (which I hate) but weigh less,I have one of the station porter trolleys they aren't expensive,you can get one for £20

Thank you I just got my son to move the potted acer I have under a canopy. No way I could have picked it up.