Climbing hydrangea

Question: Planted this climbing hydrangea at least 15 years ago.  It was very small & grew into a big beautiful bush that my husband had to build a new trellis for to accommodate the size. It’s always been healthy until this summer when we started to notice dead leaves & some dried up branches in front. I walked behind it & discovered tons of dead & dying branches. We tried extra deep watering the roots w a sprinkler thinking maybe the extreme heat & little rain was the issue but it still looks unhealthy. Any thoughts or ideas??

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied August 27, 2024, 11:01 AM EDT
response: Hi,  To our knowledge there isn't anything specific that Climbing Hydrangea have problems with, besides Asiatic Beetles chewing the leaves. It may just need to be thinned a little. You can just prune out the old dying branches as needed. If you can, try to get down to the main trunk(s) and see if you notice any burrows or chew marks. You may have to dig a little under the ground level to see. Maybe a vole has chewed on the roots causing some die back. It would be a nice hidden habitat for them.  It could be that it had some drought stress from this summer and last and if there are large trees nearby the roots of those could be getting most of the ground water during rain events and smaller shrubs may need additional irrigation. Other than the branches that are dying the foliage looks clean and healthy. If you notice any signs of problems in the main trunk(s) feel free to send additional photos. Continue to monitor for watering needs by feeling the soil at the base of the plant about 6 inches down and watering deeply about once a week if we haven't had substantial rain. Even if we have had rain still check the soil as it may not be reaching the roots well enough. Also once the leaves fall off after a freeze you can be able to see better if there are burrows around the base.  Emily

responder: The Question Asker Replied August 27, 2024, 1:13 PM EDT
response: Thank you for your quick and thorough response. This is right by my neighbor's fence and they have a huge pine tree and black walnut tree right behind so maybe they are sucking up the water, as you said. I am going to water deeply more often and I trimmed the dead wood so hopefully that will help. Did not see any evidence of voles but I know we've had them around in the past. Thank you again! On Tuesday, August 27, 2024 at 11:01:41 AM EDT, Ask Extension wrote:

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied August 27, 2024, 2:50 PM EDT
response: Yes it could be the water then. Many plants have struggled between last summer and this summer with drought and heat. The Pine and Walnut sounds like they are causing some root competition for water needs so irrigation is key! You can put your hose on a shower setting or slow trickle without a nozzle and let it run at the base for about 15-20 minutes about once a week when we don't get substantial rain.  Emily