A couple of months ago my friend Danielle made herself and her family a wicking bed based on a bathtub which had been thrown out. The idea came about as a result of our sustainability circle discussions and it was to made using as little money as possible. She managed it for the grand total of $3.50! The only monetary cost involved was a top layer of potting mix over compost from the chook yard, everything else was found. All plants were grown by her from seed. It sounded like such a good idea and I thought I would give it a go.
Also, my next door neighbor had great success with butternut pumpkin in her front yard last year and I thought I might give it a go this year. A wicking bed would be the ideal platform to give it a go with. I had a bathtub or two left over from my previous aquaponics attempt so that wouldn’t cost me anything, but would I be able to pull the other stuff together?
First I had to fix the bath. Ordinarily all you would need to do to make the bath watertight is to put the plug in, but I had taken out the drain plug fitting and installed a flange to take the inside pipe of the bell siphon. The flange was in pretty good shape but I tightened it up anyway and applied some silicone sealant just to be sure. I was able to pick up a blanking plug from the hardware and once I gave it a goodly dose of Teflon tape and screwed it home tightly, thus sealing the hole.
Before attempting to fill the bath, I wrangled around into its final position in the front yard and set it up level on bricks. Moving the thing once full would have been a much more daunting proposition, especially seeing as we had to turn it sideways to get it through the garage!
The material which goes in the bottom of the bath to form the reservoir and keep the growing medium up out of the water is usually either gravel or wood chips. I didn’t have any gravel but I am going to replace the woodchip mulch under the citrus trees in the backyard so I was able to scrape up enough bark from there to do the job. The bark had been exposed to the weather for a couple of years and so it had the added advantage of any tannin or other nasties in the bark being already leached out. The bark went into the bottom of the bath.
Once the bark was in I knew where the drain holes needed to be so I drilled them in. As usual with a larger hole drilled into steel I started off drilling a 1/8” pilot hole followed by the main ½” drill hole. Drilling into the enamelling on the side of the bath can be a bit tricky because its smooth surface can cause the drill to slip out of place. The effect is reduced by drilling a pilot hole, but if you still have problems a bit of adhesive tape over the area to be drilled will allow the drill to bite.
With the holes now drilled it was just a case of filling the rest of the bath with the growing medium. I had recently been offered some mushroom compost as a freebie, so that is what I placed in the rest of the bath. Once the mushroom compost was in place I mulched the bath with chook shed straw and planted it out with some of our seedlings, then filled the reservoir with water.
The only cost was the original cost of the wood chips, so I did OK!
A month or so later........
