Hi! I bought this tree two months ago. It was in a great shape. After several weeks in my backyard, the bottom leaves started turning yellow and the edges turned brown (with circular pattern, see pic) and eventually fell down. in the past week, some edges also turned red. The browning is now progressing up the stems. Is this Pierce’s disease? I did not see yellow halo around the brown edges though.

I live in the hilly and foggy part of San Francisco where wind could be brutal sometimes. The grape tree is in a big pot in a sunny spot in the backyard (maximum 6 hours of sun on a good day and 3-4 hours of sun on a typical SF summer day). Our garden is bushy with several big trees around.