There are a number of watering methods that have proven to be effective in the home garden. In this article, we will focus on one that emphasizes conservation and yet will promote lush and vigorous growth, no matter what varieties of plants you grow.
Promote Healthy Growth
The Deep Watering method has proven to save water and encourage plants to develop strong, active root systems. It’s basically very simple – you irrigate less often, say once every 1 to 2 weeks, although each time you irrigate more deeply.
For example, you have flowers or vegetables that have been in the ground for at least a month. When the plants have started to put out new “top” growth (new leaves or buds), you know they’ve acclimated to their environment.
Tip: Seedlings and fresh plantings (less than a month old), will always need more water until their root systems have started to expand and become established. Wait to start a deep watering program until your plantings start to show new growth. Even then you’ll want to slowly introduce them to this system.
Tip: Plants in hot, sun-drenched areas of your garden, will generally need to be watered more often, but you can off-set this by choosing plants that are “drought tolerant.” Cooler, shady areas will need much less water.
Take a few minutes to till or loosen the top one-inch of soil in the plant bed. Be careful around newer plantings, as some of the roots will be nearer the surface and will be fragile.
Deep watering will encourage the roots to go deep, looking for food and water, which is exactly what we want them to do. Loosening the top one inch of the soil will allow the water to penetrate and not run off.
There’s no need to be too fussy about tilling at this point, all the “hard” work was done when you prepared the bed for planting and will carry you through the entire growing season.
Tip: A good water nozzle is one that breaks the water flow into multiple, gentle streams.
Adding a good mulch on top of your garden bed, about 1 to 2 inches thick, is a good idea when starting a deep watering program. A mulch will help in retaining moisture and will protect roots from temperature extremes. Also, as an added benefit, will help keep weeds down to a minimum.
Start watering at a point in your yard that you can work your way back to. Slowly work your way around your garden, making sure to thoroughly water each individual plant, and any open or unplanted area around them.
In a typical 10′ x 3′ bed, you may spend 5 minutes watering, then slowly work your way around the rest of your garden.
Now you’re done for about a week, depending upon the weather. As you condition your plants to a deep watering system you will slowly stretch the length of time between waterings.
Your goal is to drive the water deep into the ground, and thoroughly saturate the soil to about 12 to 14 inches in depth. This will create a reservoir of moisture below the roots.
As the upper part of the bed dries out the roots will naturally seek the water that’s stored below them. This encourages a deeper root system which is healthier, and that is better able to tolerate low water conditions.
When you first start a deep watering program, you’ll want to keep an eye on younger plants, and plants in hot areas of the garden.
If you notice plants starting to wilt, water them deeply again. Over time you will find that watering twice, or even once a month will be all an established plant needs, depending upon specific species or variety of plant.
Low-growing annuals like pansies will have naturally shallow root systems and although a deep watering program will encourage deeper roots, any plant with a shallow root system will naturally require more regular waterings.
You can off set this tendency by planting annuals in cooler areas of your garden or using taller plants to shade surrounding areas.
In essence you’re creating a small micro-climate to protect more sensitive plantings. Additionally, annuals generally need about 1 inch of water per week.
As with most gardening activities, you may need to adjust this process to suit your particular growing conditions.