Question
I live in Washington state and am looking to build a 1.5'-2' raised bed along a backyard cedar shadow-box fence line. We have terrible, rocky soil that prevents us from planting directly in the ground and have a very small, narrow backyard forcing us to use the fence line for garden space.

I would like to use stone/rock for the front of the bed. I am looking for advice on how to best prepare the fence line to support a raised bed. With the soil and the damp northwest environment, I am concerned about fence board rot and need something to hold the soil in preventing it from seeping through the boards and down the hillside behind our yard.

Any suggestions would be most helpful. Also, as this will be my first DIY raised bed with stone/rock, any suggestions for that would be great! Thank you!

Answer

Garden wall with natur   I once did a project similar to this but in a larger yard at a customers request. I can't say that building up in front of a fence is a great idea and I really wanted to do, but it can work. Cedar is a great way to start. It is definitely less prone to rot than other types of wood.

After building the wall we purchased some plastic sheeting and stapled it to the back wall. This was to prevent moist soil from being held directly against the wood.

The downside to using this method is that it is almost impossible to keep 100% of the moisture from seeping in between the plastic and the wood.

I would expect the life expectancy of the wood behind the garden to be about 10 to 15 years with cedar and a plastic liner, but I am not an expert on wood.

No matter what you do, any project will have a life expectancy. Always try to have an easy renovation plan in case you do have problems.   

For example,

having an inner replaceable line of boards between the garden and the fence might be one option for you. This will keep the soil from creeping under your fence boards as well. This way you won't have to replace the whole fence.

How to build a small stone wall is the fun part. Here is a helpful article full of tips.

http://www.dream-yard.com/stonewall.html

Best of luck to you.

If there is anything else I can help you with, please feel free to contact me again.