This self watering system for pot plants is very useful if you will be away for a while and have pot plants that need watering. The materials are very inexpensive and can be assembled and set up in a few minutes. You will need a 1-2 litre soft drink bottle with plastic cap, a length of 3 mm internal diameter clear vinyl tubing, 2 x 3 mm one way valves (obtained from ebay for a few cents each) an electric drill with 4.5 mm drill bit, a suitable water reservoir and a stake to secure the tube in the pot plant. Assembly is simple and skill level need is low.
Follow this link to to see a detailed demonstration: