In the post on the emergency pop bottle drip irrigation setup, I mentioned you could apply the same idea for your container gardens. The idea for the pop bottle drip irrigation setups for your container garden has been around for a long time and is a great use of empty plastic bottles in the garden.
In the post I stated that I don't like the method that suggests you cut off the bottom of the pop bottle and insert it upside into either the ground or in your container garden. Here is an example of the method I don't like.
It works well, but the large opening allows for garden debris to collect in the water reservoir very easily as you can see from this picture.
I prefer the method, of leaving the pop bottle right-side-up and and poking the small hole(s)s in the bottom of the 2 liter pop bottle, because then I can screw the cap back on and keep bugs, like mosquitoes, and garden debris out of the water reservoir-- like is shown in the first image in this post.
Another benefit of keeping the soda pop bottle drip irrigation setup right-side-up; If you use a water-soluble fertilizer you can add it without worrying about pets or kids having access to the water, like they would if you created the pop bottle drip irrigation with the bottom cut off and inserted upside down in the soil.