Plant watering spikes are bulblike devices that you fill with water and place into the soil beside your plant so that the water is slowly released into the potting soil. People often use plant watering spikes when they are going on vacation or will be away from home for an extended period of time. While you can buy plant watering spikes at a garden centre, you can also make them yourself using water bottles.
Wash and rinse the inside of your plastic water bottle.
Use a sharp knife to cut the bottom off of the plastic bottle. A serrated knife would work best for this.
Use an electric drill and a small drill bit to drill between four and eight holes into the cap of the plastic bottle. The water will come out faster when you drill more holes.
Dig a hole next to your plant that is deep enough so that a third to a half of the bottle is buried. Place the bottle top-down in the hole and push dirt around it so that it is secure.
Pour water into the bottle until it is full.