Watering your Garden

Gillian Sandeman

Thorough watering in the heat of summer can be time consuming and expensive, but there are techniques and equipment which will help use time and precious resources more efficiently.

Keeping plants well watered and therefore healthy when there is little or no rain seems very simple: just use the hose or sprinklers for a little while daily. But strong plants, with the ability to survive lack of rainfall and other environmental hazards, are plants with healthy root systems that go deep into the soil. Although the top few inches of the soil may have dried out, plants whose roots penetrate the deeper moist soil will not only be finding water but also be able to use the dissolved nutrients. Shallowly watered plants, on the other hand, leave the roots vulnerable to scorching in the hot sun as they reach upwards for the surface moisture. Plants in shade can survive with less water.

As a general rule it is better to water less often but deeply. Lawns and vegetable gardens need 3 centimetres or a little more than one inch a week, flowers somewhat less. To check how long it takes for your sprinkler to provide the necessary amount of water, mark off an inch in depth on some cans, set them around the lawn and vegetable garden until the water reaches the required depth. Then, if there is no good rainfall for a week, run your sprinklers for the needed length of time and resist the temptation for a daily watering, even if your neighbour stands in her front yard every day, hose in hand, sprinkling the lawn and flower beds for ten minutes every day and expects you to be there too to chat. Go for the conversation, but leave the hose behind. Automatic timers which attach to the hose tap are useful: one with an automatic faucet shut off costs less than $20 and an electronic timer for less than $40. If you have a very large lawn you might want to consider a ‘walking sprinkler’ that allows you to cover the whole lawn equally. This useful gadget follows a path you lay out with the hose. The water pressure powers the spray arms and the gear mechanism. It will pull up to two hundred feet of hose and covers a fifty-foot wide path. Soaker hoses are an economical and efficient help in vegetable and flower gardens. Because the water is fed directly from the hose to the soil surface much less is lost by evaporation: they can use up to seventy percent less water than a sprinkler. To concentrate the water for a particular plant the aqua spikes which attach to large pop bottles are useful. You can water and feed at the same time if you add a soluble fertilizer. A good covering of mulch around flowers, vegetables, shrubs and trees will help conserve water and provide some nutrients as it breaks down. Rainfall often does not reach plants under an overhang or close to a fence or wall. Watering systems that attach to a fence or wall are an efficient way of watering these areas.

The obvious, and important, exception to the ‘water less often’ guideline is watering newly seeded lawns, transplanted seedlings, shrubs and trees and anything else that is new to your garden or that you have moved to a new position. Mist seedlings once or twice a day until they are sturdy young plants. Do not direct powerful streams of water on small tender seedlings. A must for the careful waterer is a nozzle for your hose that will allow you to choose from pressures ranging from a mist, through a gentle spray to a hard stream. Shrubs, perennials and annuals need to be watered in well until they too have established good roots in their new homes. Trees, with their large root systems, need special attention for up to two years.

Plants in containers are the thirstiest of all and need to be watered once or even twice a day. If possible do not place them under the eaves where they will not benefit from rainfall, if and when it comes. As rainwater is the best water for plants, use water barrels that collect water from downspouts for your containers and thus conserve well or tap water. If you have to use tap water, a deck watering kit that attaches to a tap is available. Last summer we installed a gravity feed system for the flowers on our deck using a water barrel and a hose system. The search for efficiency and conservation in the use of water is a continuing one.