I'm building some wicking planters. Recently, I ran across an interesting discussion of how potting mix should not be peat and compost based, as this tends to go airless and break down, but should instead be bark chunk, granite grit, peat and perlite based, which provides for much better areation and root growth. However, would this wick well enough to be used in a wicking planter? The main drawback of the airy mix is the frequent watering, but this should be eliminated by the wicking container. Also, fertilizer has to be added, but really a compost based mix still needs fertilizer, so they are even there.
What do you use in your wicking buckets/ containers?
In my wicking beds I use a sandy loam over a layer of sand. Between crops I add compost and keep it all mulched really well. It wicks really well, the loamy layer is about 18" thick and the water appears to wick up to the top but weakly. This keeps the soil moist but does not get through the mulch which would allow the water to evaporate.