Creating your own self-watering system for standard urban planter boxes is an efficient way to maintain healthy plants while conserving water. This simple DIY project requires basic materials and can be completed in an afternoon. Here's a step-by-step guide to building an effective wicking bed system.
First, gather your materials: a standard planter box (with drainage holes), a plastic container or PVC pipe for the water reservoir, a piece of landscape fabric or geotextile, a length of PVC pipe for filling the reservoir, potting mix, and a drill.
Start by preparing the water reservoir. This will be located at the bottom of your planter box. Use a plastic container with holes drilled in the top, or create a reservoir using perforated PVC pipe laid horizontally across the bottom. The reservoir should cover about one-quarter of the planter's total depth.
Next, create the wicking column. This is a vertical column that extends from the reservoir up through the soil. You can use a section of PVC pipe filled with gravel or a specially designed wicking basket. This column will draw water upward from the reservoir to the plant roots through capillary action.
Install the fill tube—a piece of PVC pipe that reaches from the top of the planter down to the reservoir. This allows you to add water directly to the reservoir without disturbing the soil. Drill a small overflow hole about one inch from the top of the planter to prevent overwatering.
Place landscape fabric over the reservoir system to separate it from the soil while still allowing water to pass through. Then fill your planter with quality potting mix, being careful not to compact it too much. The soil should reach about two inches from the top of the planter.
Finally, plant your seedlings or seeds as you normally would. Water thoroughly from the top for the first week to establish the plants and ensure the wicking system begins working. After this initial period, you can primarily water through the fill tube, checking the reservoir level every few days.
This self-watering system is particularly effective for urban gardens because it reduces water waste through evaporation and provides consistent moisture to plant roots. The reservoir typically needs refilling every 5-10 days depending on weather conditions and plant size, making it ideal for busy city dwellers who want to maintain productive container gardens with minimal maintenance.