Q.bottle brush tree
My bottle brush is shedding lots of its green leaves. It’s now the end of July. What’s happening and is anything wrong?
If your average temperatures this summer have been high, your tree is probably crying for more water, especially if it's still young.
Some of the most common reasons for leaf drop are shock, weather or climate conditions, pests or disease. You should check the leaves carefully for signs of pests or disease, and this article will give you some additional information on identifying and correcting other possible causes:
https://www.gardeningknowhow.com/garden-how-to/info/plant-dropping-leaves.htm
This article provides some tips on growing Bottle Brush trees:
https://www.gardeningknowhow.com/ornamental/shrubs/bottlebrush/growing-bottlebrush-plants.htm