Wick systems can be quite effective for extending the period of time between waterings. They are usually set up with a water reservoir below as
@CrazedHoosier has shown. It is the most basic of all self-watering systems and the least expensive.
Wick systems work best with plants that prefer soil that stays moist, such as a Peace Lily, but not very well with succulents that need soil to get quite dry.
To be effective, the wick should be pushed through the bottom drain holes with one end dangling in the water reservoir. The key is how far into the rootball you push the other end of the wick. That will determine how far up into the rootball the water will rise.
Unless you have a specific need to extend the interval between waterings, it is probably best not to use the wicks.
