I am trying to decide what to do with my lawn border, there are several things to consider. This is my backyard in Phoenix where lawns take extra water to keep them healthy. I have a brick border where I had planned to keep the grass contained in. When watering trees it has encouraged grass growth around the trees.

So the options are let the grass grow all the way to the block wall and adjust the sprinklers to water against the wall. The problem with this is the sprinklers and water hitting the block wall will eventually destroy the block wall and cause expensive repair.

I do not want to spray the grass with grass killer right next to the trees because of fear that it may damage the young trees.

One other option I had thought about is putting several inches of mulch on the ground around the trees leaving a border around the wall where there will just be mulch. The question with this, will mulch be enough to kill persistent bermuda grass that is thriving around the trees?

I am open to other options of what to do around this area taking into consideration my concerns of the block wall and the young trees.

Please offer your suggestions.

Thanks.