Houseplants are a joy to have around, bringing beauty to our lives. They are also useful for absorbing carbon dioxide in a room and releasing oxygen for your breathing pleasure. Plants are also a responsibility. It's easy to forget to water, or to overwater, and kill the plants you love. Self-watering products are available at your local garden center and online, but can be costly if you have many plants to care for. However, they are easy and inexpensive to make yourself.
Gravity and Wick Type
One type of self-waterer you might find at your garden center works on the laws of gravity and of water finding its level. For each waterer you will need a clean quart-sized jar and enough cotton wicking to reach from the bottom of the jar to the top of your plant's soil. You will also need a brick or similar object to set the jar on that will put it at a level higher than the plant.
Begin by watering your plant well. Fill the jar with water and set it on a table, brick or box to make it slightly higher than the plant's soil surface. Place one end of the wicking into the jar, all the way to the bottom. Place the other end on the soil near the plant. As the soil dries out it will draw on the moist wick, pulling water into itself. By osmosis, water moves from the highest concentration to the lowest concentration, keeping your plant hydrated.
Another self-waterer, which can be located right inside the plant's pot, is the globe or funnel type. While this version might not be as decorative (unless you want to cover the outside with nontoxic painted pictures) it should work as well as the ones you can buy for up to $10 each.
Save your 1- or 2-liter soda bottles, along with their lids, and clean them thoroughly. Use a drill or nail and hammer to punch four or five good-sized holes in the lid of each bottle. With a sharp serrated knife cut off the end of the bottle. Twist on the lid. Dig a hole beside your plant and bury the bottle, lid side down, about a third to halfway. If your planter has several plants in it, you can bury the bottle in the midst of them to hide it. Fill the bottle with water, and your plant will have a ready source to turn to when it's thirsty.