Climbing hydrangea browing
The leaves of your Hydrangea anomala petiolaris aren't drooping, so I don't think you have a watering issue. This plant thrives in enriched, fertile, well-drained soils. It tolerates full sun in cool climates with consistent moisture. Avoid hot, humid conditions. Prune annually after flowering if you wish to control size. Plants typically do not flower for 3-5 years or more.
I think your browning leaves may be caused by too much sun and heat. The plant appears to be is a very sunny sight, and the brick wall radiates even more heat back to the plant. And the 90-degree temperatures we've had the past week or so no doubt contributed to the browning.
Be sure to keep the plant well hydrated (weekly and more in extreme heat) and watch to see if the browning continues. You may want to consider relocating it to a cooler sight while it is still relatively small.