discolored branch core and curling leaves-prunus mume

Question

I have a young prunus mume tree that had somewhat curling leaves when I brought it from the nursery. It is worsening and now almost all of the leaves are curling and some developed discoloring on one lateral side then died. I clipped the dead leaves and ends and found that some of the inner core of the clippings were discolored brown.

Some facts: I watered it and kept it in its 1-gallon container 1 week then planted it in a 2″ hole with compost, planting soil and existing soil, well watered with the root flare at soil level in full sun. The 3′ basin around it had been spaded.

Strangely, the leaves around the inner part of the tree seem to be curling first and most.

Any advice? I live in Southern California and the tree is a cultivar called Prunus Mume Miyazono.

Thank you!

• 
• 
• 
• 

Answer 1

Indeed, it does not look healthy.

It could be stressed, as you mention you bought it in this condition.
You can't rule out a fungus or pest issue, as prunus trees are susceptible to some diseases.

I would suggest taking some leaf samples into your County Extension Office for diagnosis.
https://www.gardeningknowhow.com/extension-search/
https://www.gardeningknowhow.com/edible/fruits/plum/plum-tree-diseases.htm
http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=d115