Thinking of creating a container garden? You can design a planter with a built-in reservoir to continually water the soil while you're away. All you need is a plastic drink bottle around the same height as your planter.
DIY weblog Dabbletree shares a design for the reservoir, noting that you just need to cut the bottom from the plastic bottle and remove the cap. Partially fill the planter with soil and add the bottle. Continue to add soil to the outside of the bottle until you reach a few centimetres below the top of the planter and add new plants in the round shape surrounding the bottle.
Planter DIY Water Reservoir [Dabbletree]