Last week I wrote about how to successfully plant in the dry summer months and I promised this week to discuss how to keep our landscapes thriving (not just surviving) as we shift to drier, hotter, and longer summers. As a side note, don’t let this recent “rain event” lure you into complacency about watering. At best, it only moistened the top ½ of the soil, which for the most part only keeps the dust down.
If you have any doubt in your mind that our summers are getting drier, you only have to look around town at all of the dead arborvitae (Emerald Green) hedges to confirm that not applying extra water in the summer months has lethal consequences. And if you are reluctant to spend money on your water bill, I would submit that replacing dead landscape material is a whole lot more expensive. Our landscapes add anywhere from 5% to 15% to the value of our homes, and just like keeping our house siding painted or roof repaired, maintaining our yards helps protect our investment.
While we seem to get plenty of rainfall in the winter months, that’s no longer the case in the spring and summer. We are currently 6 inches below normal, which is not a good omen for the coming summer months. It’s time to start adding some supplemental water to our yards.
While not everything in the yard needs water daily, shallow-rooted plants (like annuals, perennials and container plants) should be checked every day and watered accordingly. More established trees and shrubs may only need a good soaking once or twice a month. If all those dead Emerald Green hedges had been given a deep watering once in July and once in August, they would be just fine now. Plants can’t whimper like a pet who’s water bowl is empty, and unfortunately, by the time most homeowners realize their plants are in distress it is too late to save them.
There are two things that will help us be better waterers… One is mulch and the other is a proper sprinkler. Adding an inch of mulch to the soil surface will help hold in moisture and reduce the amount of evaporation. Mulch can be free (like arbor chips or well-rotted manures), or purchased screen compost, either bulk or bagged. Spread it one-inch or thicker, except for right around the base of the plants - you don’t want them to rot, so keep it low so the stems can breathe.
As for sprinklers, the big dilemma is that water comes out of the end of the hose faster than it will soak into the soil. Oscillating sprinklers do a pretty good job of slowing things down and so do impact heads (think rainbirds). But the best “sprinkler” for our heavy clay soils is either a soaker hose or a drip system. You can turn them on when you go to work and turn them off when you come home without worrying about water going everywhere. Once or twice a month may be all you need to keep your garden happy.
So, the secret to successful watering is to first probe the soil with a shovel to see how dry it really is, and then to apply water slowly and deeply so it can soak in rather than run off down the street. And finally, applying mulch to help retain the water. Doing these things will help protect your landscape investment and get the most value out of your water usage. That’s good advice for the budget as well as the plants!
