Elaine Sanders: Waterwise practices for home gardeners | Elaine Sanders ‹ Gardens and Landscaping
When it comes to watering plants, are you the type to wait until foliage resembles the texture of a baked spring roll before reaching for a watering can? Or the one who waters the garden ‘to relax’ while unnecessarily drenching everything in sight like an eager firefighter? Whatever your habits, watering doesn’t have to be a chore if it’s done right. Besides, it is counterintuitive to waste natural resources while caring for plants.
So how much water do plants really need? The answer depends on a variety of factors, including soil type, sunlight conditions, time of day and year, planting location, and plant type. That considered, most plants only require a few centimeters of water per week, an amount easily provided by a short downpour, typical of late. Important to keep in mind is that infrequent, deep watering is better than frequent, shallow watering. The latter encourages root growth near the soil surface where plants are most susceptible to drought damage.
Water at the roots
Plants don’t absorb water through their leaves so watering at the root zone rather than overhead, where water is lost to evaporation, is not only more efficient, but also prevents fungal diseases from developing on leaves. Soaker hoses and drip irrigation systems slowly emit water right at the soil level over an extended period so are especially suitable for vegetable gardens which require a regular watering schedule.
Watering potted plants
Containers of annuals and vegetables — especially smaller ones and those in porous clay pots — require supplemental, even daily watering during hot spells. Rainwater rarely gets past foliage to reach the soil in containers. Check that plants are dry first by inserting a finger into the soil, then water them deeply until water soaks right through the drainage holes at the bottom. Self-watering pots, which are fitted with a tube that absorbs water from the hidden reservoir within the pot, allow for less frequent watering. Grouping containers together, using a quality potting soil and topping it with a fine, organic mulch also helps reduce moisture loss.
Watering garden beds
When it comes to permanent garden plants such as perennials, shrubs, and trees, watering properly during the first year of growth should promote deep root development so the plant is established and does not typically require supplemental watering. So, stop watering established perennials, shrubs, and trees; these plants’ root systems can usually fend for themselves. Think of the perennials in your garden that never require watering, peonies and for instance, or large-leaved, mop-head hydrangeas even if they are wilting on hot summer days.
One inch or 2.5 cm per week is all the water that lawns require, so either set up sprinklers with a timer or collect and measure rainwater in a shallow dish. For those with irrigation systems, a rain sensor with automatic shut off will reduce unnecessary watering. Mowing high and leaving grass clippings (which are mostly water) on the lawn can also help stave off drought as will aerating compacted lawns and raking in a layer of quality compost.
Have a rain barrel
According to statistics Canada, very few households in 2019 had a rain barrel. Many municipalities offer incentives to residents to encourage use of rain barrels, which on average hold 190 liters of rainwater. Rain barrels can be quite stylish and are easy to use when equipped with a spigot. Garden plants prefer oxygen-rich, warm rainwater over chlorinated hose water anyway. And rainwater is free. Need I say more?
Elaine Sanders can be reached at firstname.lastname@example.org