The retaining wall that I made for my mom keeps sinking. What do you guys suggest I do to prevent it from keep sinking. It rains a lot in Houston, so the dirt drifts away all the time. I hate keep having to come out and moving it for my mom. I thought that it would prevent the weeds from growing in, but it keeps getting in everytime I dug it up. Its this annoying type of grass that has really long roots. Even if I dig really deep to try to pull it up within a few weeks or a month it grows again. I'm thinking of just spraying it with weed killer, but it might kill my mom other plants. The other choice sounds safer, but also more labor. That would be to just take all the bricks out, dug everything up and put some garden tarp or other garden materials so the weed won't grow again. Everything seems easy enough, but the big problem is there this seven feet magnolia plant in the circle. The grass roots might be well under the magnolia roots or in between the roots. Its going to take awhile just to dug that plant up and trying to pull all that grass root out. What you guys suggest I do? Also can you guys give me some advice on keeping the ground level so the bricks wont sink anymore. I have a few pictures.