How do I add drainage and veggie patch to retaining wall?

[Sam131]

Hello wise gardeners! 

This is my FIRST time creating a backyard / garden, and I'm eager to learn from your expertise. I'm in need of some guidance and I'm sure your advice will be invaluable.

We are creating a veggie patch in our retaining wall along the back fence (see photo)—length 7.2m, 0.8m width and 0.5m deep. The full back fence length is 11m. but 3.8m (to the left, not built yet) will be seating. 

I need clarification on how to do the drainage, treated wood protection and soil. 

Water flows from the back neighbour, so I need to add an agi pipe. However, the wood is treated, so I also need to put down plastic. I'm confused about how to layer this.

There is a drain where we can direct water, too.

I would love to know what to put in the garden and what layer, as I need help understanding where the agi pipe goes then the plastic?

If someone could explain this to me and suggest what products to buy, I would be incredibly grateful for your help! 

And bonus if you could tell me what soil to buy for the veggie patch too 

[MitchellMc]

Welcome to the Bunnings Workshop community @Sam131. It's fabulous to have you join us, and many thanks for your question about installing a garden bed.

You'll add your agiline at the rear of the garden bed, directly in front of the retaining wall. You'll need to dig a trench along the front of the retaining wall for the length of the garden bed. The trench should be 100mm wide and around 200mm below the bottom of the garden bed. You can then lay your socked agiline into the trench. Once the agline is installed and connected to your drain, you can backfill the remainder of the trench with drainage gravel. 

Now that the drainage is installed, you can install your plastic on the walls of the garden bed and retaining wall. Then, follow this guide: How to fill a raised garden bed.

The water that transfers through the retaining wall should hit the plastic and fall into the trench and agiline below it.

Please let me know if you have any questions.

Mitchell
 

[Sam131]

Thank you so much for your advice