[supaflyz]

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.

 

[concretemasonry]

Just install the retaining wal block (they are not bricks) according the manufacturers information.

For some reason, some block in the photos are shown upside down.

Dick

 

[TooledUp]

Have you dug down below the retaining wall and then filled with slag and them compacted it?? From my experience you need some sort of base down below the wall or it will keep settling.

 

[supaflyz]

What is slag? Sorry Im completely new. Is it pebbles or stones?

 

[Kap]

The grass will always grow through those cracks. It's heading for the water source-the potted plants. You just have to be diligent about pulling/weed whacking it.

Here's what to do:

Option 1: inside the circle: take all the desired plants out. Spray all the weeds inside with roundup. It won't hurt the tree. Do it when there is no wind. After the weeds are dead, put a weedblock cloth down and cover it with an inch or two of mulch. If there are tree roots exposed, cut slits in the weedblock over the exposed roots.

Put the plants back on top of the mulch. not only will this help keep weeds down, it will look 1000% better. You will still get weeds. The seeds blow in. But they will be very easy to pull out of the mulch when you see them as they won't be able to root in the soil.

Option 2: Remove the top inch or two of soil from inside the retaining wall area and then put a weedblock cloth down and cover it with an 2-3 inches of mulch. If there are tree roots exposed, cut slits in the weedblock over the exposed roots.

 

[Kap]

As for the wall itself, as suggested above look up the mfr's instructions. You may want to consider at least two courses (layers, rows stacked) with the first one buried halfway or a little more than half way. This will slow down the grass from getting in.

 

[Kap]

Another thought-not sure what you're budget is though-would be to add a third course. If the wall was 8-12 inches high, it would hide the pots and let the foliage show. Smaller pots could be place on blocks inside.

AND this would give your mom a place to sit and be more comy tending to the plants. She might even be motivated to pull the grass as it encroaches on the wall since she can just 'sit in the garden' while working.

If you do that though, it's even more important to the wall right-which is going to require digging deeper and adding a packed gravel base.

Just follow the instructions and take your time and you can have awesome reults.

 

[TooledUp]

What is slag? Sorry Im completely new. Is it pebbles or stones?

Well, ok, that is what I call it. I am not sure what the technical term is for it, but it reminds me of like a limestone. You put that down and use a tamper, and then set your block. Find your local brick paver store and they will have what I am talking about. Just tell them what you are looking to do and they will assist you.