Coral Bark Japanese maple

(Question)

3 year old maple – 4 feet high – in well drained soil – 5/6 h of sunlight – zone 6A – approx. 1km from Lake Erie shore in Ridgeway – two thirds of crown is well leafed out with new growth, however from the main trunk several stems approx. 1-2 cm in diameter over the course of this season their vegetation would suddenly turn brown, leaves would curl and die. Did not see any evidence of insects or any disease on the leaves. Help! I do have photos but I don’t know how to upload them to your site, provide an email address and I can forward them to you. Thanks

(Answer)

It does appear that your Japanese Maple is suffering from leaf scorch. We do sometimes receive questions about this and you can see a response to a similar, previous query here:

https://www.torontomastergardeners.ca/askagardener/brown-curling-leaves-on-japanese-maple/

You do mention that the tree has good drainage, which is excellent.  Japanese Maples also grow best in partial shade. It may be that the high amount of heat we’ve had this summer has been causing your tree’s leaves to brown.  Do make sure that it is well watered during times of extreme heat, as this is when drought may negatively affect plants.

We also have published a Gardening Guide on growing Japanese Maples which you can access here:

https://www.torontomastergardeners.ca/gardeningguides/growing-japanese-maples-a-toronto-master-gardeners-guide/

Good luck and thank you for contacting Toronto Master Gardeners.