I have the most stunning Acer in my garden that is now about 14 years old. This year about only 50% of it has leaves. Is it dying? I do not want to cut it back if there is a chance it will recover and I don’t want to risk traumatizing the remaining plant. I have scraped the bark of the non budding branches and they don’t appear to be green. This is a real feature in our garden and I would be very sad to lose it. Should I try repotting it. I haven’t done this for about 5 years but I feed it and I remember reading that Acers like to be pot bound. Perhaps it was the bad wind storms earlier in the year, but previous years it has survived the winter fine. Any help or suggestions please?
the picture's a bit confusing - I see what looks like 3 separate Acers, one with red leaves and the other two are dissectum varieties, one lower than the other and at the front of the image - are these two the same plant, or separate plants? If separate, which one do you mean? also impossible to see any pot, but how large is the current pot? And what part of the world are you in please?– BambooApr 16, 2020 at 16:33
The one that has the problem is the one in the middle, the lower one and red are separate plants. It usually goes right up the fence where all the twiggy bits are. I am in the UK.– JulieApr 16, 2020 at 17:05
I have added two more photos. The pot is about 50cm x 50cm and the plant is about 2m x 2m, but the roots have rooted through the pot into the soil. This is one of the reasons that I haven’t repotted it.– JulieApr 16, 2020 at 17:13
Thanks for the extra information. I wondered how that Acer dissectum at the back had got so big if its contained in a pot! Well of course, it isn't, because it's rooted into the soil beneath through the pot...
As it's rooted into the ground, I'm sorry to say the most likely explanation is Acer dieback. This is quite common in Acer varieties (especially those in the ground) and is sometimes caused by verticillum wilt disease, though not always. Hopefully that isn't the cause, because if it is, further dieback may occur next year.
In the meantime, cut back to live wood - there is no point in leaving dead wood in place, but don't cut back too far into live wood at this time of year, just to where it begins. Given it's rooted into the soil, repotting isn't a viable option, so it will have to stay as it is - it doesn't need it anyway as it's got free access to the open ground beneath. Certainly use a general purpose fertilizer (Growmore or similar) around the base of the tree towards the end of this month - this might help to keep it going for longer and keep it as healthy as possible.
Thank you, I will try that and prey that it survives.– JulieApr 16, 2020 at 18:02
I had a Jasmin growing along the fence (rooted in the same area as the Acer) which I have just cut right back due to fungus (photo added) could this be the same fungus and if so, do you think I am I over watering the soil there?– JulieApr 16, 2020 at 18:13
not currently no, but we have had an extremely wet winter this year here in the UK up till about 3 weeks ago... very wet conditions in winter can cause verticillum wilt in Acer, but it might not be that. Just see what happens, hopefully at least the Jasmine will recover.... that cluster deposit on the Jasmine is not fungal, not sure what it is, maybe a gall or something, but cut that area out anyway. That is a very crowded corner, won't be much airflow in there...– BambooApr 16, 2020 at 18:27