Q.Bottle brush tree is brown
We had a severe cold snap in Houston last winter. By spring, my bottlebrush tree is very slow in blossoming. It does have some blossoms beginning but it is still rather brown. Should I just let it got through its spring cycle and cut away any remaining brown parts after it is done blooming?
Yes, I would wait to do any pruning or clean up until after it blooms.
Here are some articles with more information.
https://www.gardeningknowhow.com/ornamental/shrubs/bottlebrush/growing-bottlebrush-plants.htm
https://www.gardeningknowhow.com/ornamental/shrubs/bottlebrush/pruning-bottlebrush-plants.htm