top of page

Water Smart – Sub-Irrigation

Irrigation, which is the delivery of water to plants, is an essential part of gardening. Irrigation can be achieved in many ways; however, certain methods can be used to save water while supplying consistent moisture levels.

Water is essential for plants to make food, grow, and maintain their structure. When plants do not get enough water, they go through something called drought stress, and when they get too much water, they become waterlogged. Each plant has its own moisture preferences, however, the symptoms of underwatering and overwatering show up in remarkably similar ways in plants. With both under and overwatering we will see wilting, chlorosis (leaves and stems turn yellow), necrosis (leaves and stems turn black), root dieback, stunted growth, and in some cases, we will see plants flowering and fruiting. Although we usually perceive the flowering and fruiting of plants as a positive thing, plants will set flowers and fruit under extreme stress in a final attempt of survival by passing along their genetics through their offspring.

The best way to determine whether a plant is receiving too much or too little water is to look towards the soil. Since overwatering and underwatering presents terribly similar symptoms in plants, the best way to take the guesswork out of it is to observe moisture levels in the soil.

Consider the following scenario: you see yellow leaves on your cucumber plant, it’s flowering prolifically, and although you’ve watered it every day for the past week, you can’t help but think that it still looks wilted and thirsty. Before you water your cucumber plant, stick your fingers into the soil; is it dry? Damp? Soggy? If the soil is dry, you might need to use more water or water more frequently. Or you might have to move the plant into a slightly less windy/ sunny spot. If the soil is damp or soggy, try using less water or watering every other day instead of every day.

Knowing when to water and how much water to use can be stressful. However, this is where the science of capillary action comes in. Capillary action is the movement of water from an area of high concentration to a point of low concentration. Water can even move against gravity with capillary action. Sub-irrigation utilizes the science of capillary action to move water up through a reservoir into the soil as plants draw water up and out of the soil. Sub-irrigation is a method of self-watering that takes the overwhelming guesswork out of watering plants. Simply fill the reservoir every couple of days to every couple of weeks, and provide your plants with consistent moisture levels. It’s easy enough to buy sub-irrigated planters, but it’s so much more fun to build them from scratch.

The Rangeview Home Owners Association (RHOA) will be hosting a workshop where we will be building sub-irrigated planters. Within these planters, we’ll be able to grow vegetables, fruits, leafy greens, and herbs. This workshop will be held on Saturday, April 23rd from 2:00 pm – 4:00 pm. The workshop will also include demonstrations that explain how sub-irrigation and capillary action works, as well as other methods that can be applied to save time and water in the garden.

3 views0 comments

Recent Posts

See All


bottom of page