Wicking beds are commonly used in the permaculture movement, and are a fabulous way to grow healthy plants with bottom watering. When plant roots reach down for water, they grow deeper and thicker, which means more nutrient gathering and healthier top-growth.
Even better, wicking beds allow you to go away for the weekend in the summer without worrying about your vegetables or flowers.
A wicking bed showing healthy tomato plants about to bloom.
Wicking beds are created using a container with a water-proof bottom. This may need to be created using poly-plastic (cheap, but breaks down) or pond liner (expensive, but lasts.) A PVC pipe with elbow is put into the bed vertically, with a connecting PVC (with holes drilled in it) running horizontally across the very bottom of the bed. The vertical pipe should stick up above the level of the soil, and can be capped for more water retention.
Diagram of a simple wicking bed.
Once the PVC pipes are in place, a layer of gravel is added. (Make sure the wicking bed is in it’s final spot before you add the gravel.) This can be from 4-12 inches deep depending on the depth of the container. Once the gravel is levelled, a double layer of landscape fabric is added to separate the soil from the gravel. At this height, several drainage holes should be added to allow for overflow and prevent the soil from becoming water-logged.
On top of that, a rich compost mix soil is added, to a depth of 12-18 inches. (Fill the soil to the rim of the container). New plants will need some top watering until their roots are deep enough to reach the wicking mat. The reservoir is kept full by adding water through the PVC pipe until it runs out the over-flow holes.
They are fairly simple to create, and there are many ways you can incorporate this concept. Which one is best?
Good: The plastic storage tub wicking bed
Create a wicking bed out of a plastic storage container.
- A great inexpensive way to try a wicking bed
- If you move, it can come with you
- It can be re-purposed to store other things
- Drawbacks: It will be very small, so not many vegetables can be grown
- It is made with plastic, and leaching is a concern
Better: The Costco raised garden
Here is a pre-made wicking bed available at Costco.
- A waist height container allows for easy gardening without hurting your back
- This is likely the best option for people with mobility issues
- The garden can be moved
- Drawbacks: It’s pricy
- Again, it is made with plastic, so leaching is a concern
- The gardening area is not very big, so not many vegetables can be grown
- The reservoir is also shallow, so it may not hold enough water for a long period away.
Best: The built in cedar wicking bed
A built in cedar wicking bed is attractive and functional.
- Attractive
- Can be made to any size, and customized to fit the available space
- No plastic, so leaching into the soil is not as likely
- Rain barrel overflow can be directed into the PVC pipe
- Drawbacks: More expensive
- Woodworking skills required
- Best for a permanent garden
Cedar wicking bed with built in lattice trellis.
The rain barrel overflow is directed into the wicking bed.
Have you thought of using a wicking bed to grow vegetables or flowers? Do you worry about going away in the summer?