These are my friend Lisa's herbs (peppermint, thyme and lavender) enjoying the view in Bay Ridge, Brooklyn. They're new plants just planted. We'll watch them grow. If you're nearby, I'll give you a pop bottle planter and some potting mix and you can start your own herb garden. Just ask.
Once you see one, you'll understand how easy they are to make. You won't find a better sub-irrigation (aka "self-watering) planter (or any other kind) on the market and they're free! Do you think your plants roots are as happy in those clay pots or grow pots you're using? Notice how the reservoir creates a humidity chamber.
Yes, sub-irrigation is counter-intuitive for gardeners who have been constantly brain washed about the necessity for drench and drain watering. Most of this misinformation originates from the USDA Cooperative Extension Program. Unfortunately their information about subjects like houseplants and personal food production in containers is woefully out of date.
Pop bottle sub-irrigation is really no different than the method used in all sub-irrigated grow boxes (vegetable planters). I don't know of a better way to teach yourself and your kids how sub-irrigation works.
Do some good for your personal environment and the environment at large. Recycle plastic pop bottles into sub-irrigation planters like these and grow some food, foliage or flowers. Make one for a friend too! On second thought, make some for all your friends.
Pop bottle planters offer the best chance of breaking through the wall of ignorance about sub-irrigating container plants. Help create the pop bottle planter chain across the country...around the world. I started a Flickr set and will probably start a Flickr pop bottle planter group in the near future.