Wicking beds

Veggies love wicking beds because they a provide low-stress environment of constant, optimal moisture, good for soil life, and good for your plants. You’ll get more food, from less space!

In wicking beds, the surface of the soil is relatively dry, making it more difficult for weeds to germinate. That's because moisture wicks up from the reservoir of water at the bottom of the bed.

It's been suggested wicking beds use of one third to one half less water than a conventional raised bed. Which means that we're watering much less often,  even during heatwave conditions. And that's ideal where we rely on volunteers to tend the gardens.!

Acknowledgements

Thanks to each of these people who donated "stuff" or their time to make the wicking beds happen:

Molly Saunders, Brad Emmert, Joshua Heazelwood, Bill Gannon, Jim Field, George Whiley, Bernie Weckmann, Samala Fritz, Rhettro Roofing CQ. 

Step 1

Set your bath into your raised bed. Use a spirit level to ensure it's level in both directions - across it's length and width.

It will hold a resevoir of water, so it's important that it's set level.

Step 2

Drop a length of 50mm PVC into the drain hole. I needed to use a file to open up the drain hole a little.

I used "Selleys Knead it" to seal around the PVC and keep it watertight.

For extra strength, I pushed the PVC through the drain hole about 50mm. 

Step 3

I've added old bricks to the base to act as a void. We had the bricks, but you could use anything that you have available that will act as a means to support the geotextile fabric/shadecloth that will prevent the coarse sand from filling the reservoir.

I've seen breadcrates, milk crates, round stones and galv mesh used to hold use the shadecloth and make the water reservoir.

Step 4

Drill a drain hole in the 50mm PVC. Once the water reaches the top of the reservoir, it will drain into the PVC to drain away. Wrap a pieces of shadecloth around the pipe to prevent coarse sand washing away.

Step 5

The filler tube needs to go in. It's a bit of 50mm slotted agricultural pipe, that will allow fairly quick filling of the reservoir.

Step 6

Geotextile fabric or shadecloth can be used to cover the reservoir. It's there to stop the coarse sand from filling the void where the water sites. As the bed is filled with coarse sand, you can see the additional wicking areas between the bricks and bath sides.

Coarse sand was packed in quite firmly at the bottom to give good wicking capacity

Step 7

Coarse sand to a depth of about 200mm. Quality garden soil to fill the bath very close to the top.


Step 8

Ipomea aquatica (Kang kong) and Aethionema cordifolium (Lebanese cress) is the planting here - both marginal aquatics. They'll be watered from above until they start growing and send some roots down.

From there, we'll fill up the reservoir, and let moisture wick up from the bottom. Marginal aquatics should love the available moisture.

Plenty of straw mulch to preserve moisture and control weeds.