We planted a bottlebrush tree about a year and a half ago in the Phoenix area. It has been doing great. we had seasons with the blooms but now at the end of the heat of the summer it appears to be dying from the top down. There are two main branches that grow out the trunk and it appears to be only happening off the one side. We have recently had some good monsoon rains so I’m not sure if it’s over watered or under watered or needs some nutrition .
I have had several gardeners report issues with Bottlebrush Tree in the extreme heat in areas this summer.
Both the heat, dry weather and then heavy rains could be the issue.
Make sure the soil is properly watered and that the soil is well draining.
This is the key to success for this tree. My experience is that this tree can die off quickly.