If you’re looking at more efficient ways to use water in the garden, this upside-down watering invention might just be for you. 

Wicking beds are like gigantic self-watering pots, they’re designed using an underground water reservoir which waters the plants from below rather than above. This significantly reduces evaporation and creates better growing conditions for the plants.

You can build a wicking bed out of any type of container, so keep a lookout for recycled products. Other essentials are piping, gravel or other aggregate, matting and soil. But, if you’re not up to building one yourself, there are plenty available for purchase at retail outlets.

Remember to always do your research and go with what works for you. While wicking beds may cost a little more to set up, they’ll reap the rewards in no time with fresh produce and huge water savings! 

A wonder in the garden

The B4C* team have built a corrugated iron wicking bed to grow vegetables and other plants. Below is a list of other materials they've used (from the bottom up literally): 

  • impervious membrane liner PVC (aka Geomembrane liner) and Butyl rubber liner (think fish pond lining)
  • rock and gravel to about 30cm in depth
  • geofabric laid over the top
  • scoria (volcanic rock)
  • geofabric again
  • standard potting mix around 30cm in depth
  • sugarcane and bark mulch

 Tips:

  • Include Alyssium plants. They are a shallow rooted plant (not edible) and an important indicator to how much water is available.
  • A wicking bed can have a long life, so make sure whatever you use is sturdy enough to hold its shape.
  • Geofabric allows water but not soil particles to pass through the garden bed layers.
  • Don't let the water level drop too low as it will break the wicking cycle. You'll need to reset by either watering the plants from the top or filling up the reservoir to the top.
  • Mulching all year round helps retain soil moisture, temperature and aeration. Its benefits will be seen more frequently in the summer months protecting the topsoil layer.

*B4C is a volunteer group who support nature conservation and environmental education and awareness. They partner with many organisations and the wider community to build a web of green across the region.

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