Free Press columnist Georgeanne Davis


Free Press columnist Georgeanne Davis

I’d like to not think about watering at all. I recall a time in the not-so-distant past when one could plant a garden, water-in seedlings until they’d recovered from transplant shock, perhaps pay a bit of attention to newly germinated seeds, then sit back and let Mother Nature take its course. But the climate in Maine and everywhere else has changed enough that if you plan a garden, you’d better plan on watering it.

According to the Maine Climate Council’s most recent report, of August 2020, statewide annual precipitation (rainfall and snowfall) has increased by 6 inches since 1895, mostly due to increased rainfall in summer and early fall. So you’d think we wouldn’t have to water, but alas, though we get wetter and wetter, warming temperatures intensify the hydrologic cycle, which means wetter wet periods and drier dry periods. The rain just won’t cooperate and fall gently every other evening, as we’d prefer. Fortunately, there are tools and systems available to give your garden the water it needs, ranging from dunking a watering can into a rain barrel to drip or soaker irrigation systems operated by solar-powered timers. The hard part is selecting one for your particular garden.

Before discussing how to water, here are a few tips on deciding when to water. Since conventional wisdom says your garden should get about an inch of water a week, you need to know just how much it received during a rainy period. Sometimes it can seem a lot of rain has fallen, but when you dig down in the beds they’re surprisingly dry. An inexpensive rain gauge, pushed into the soil like a garden stake or mounted on a fencepost, can tell you instantly how much that last rainstorm delivered. If you need to water, plan on doing so once or twice a week and delivering enough to really soak the roots of your plants. Frequent shallow watering only leads to weaker root growth and evaporation.

There are basically three kinds of irrigation systems: overhead, drip, or soaker hose, and each has its benefits and drawbacks. The truth is that within a vegetable garden, various beds and zones may have different needs and can benefit from more than one system. Overhead watering, whether from a hose or sprinkler, is great for greens and root crops, which aren’t susceptible to water-borne blight and fungus. Overhead watering is also good when starting seeds outdoors, as you can evenly water an entire bed, making it ideal for seed germination. It’s also a good method for new transplants. Since there are no hoses in the garden beds, it’s easy to weed using a hoe or tool. And, for those just beginning to garden, a sprinkler system is one of the least expensive irrigation methods because one sprinkler can serve many plants. It’s also simple to set up; if you need to, your sprinklers can be moved around to different zones. A good spray on plant stems and leaves can also wash away garden pests such as aphids and spider mites, and during dry, dusty, hot spells, a gentle spray also removes dust build-up. Drawbacks to using sprinklers include wasting water on paths and wetting of foliage on plants prone to foliar diseases, as well as putting you, the tired, time-stressed gardener, in the position of standing around watering when you need to head off to work or would rather be kicking back at the end of the day.

Drip irrigation is a great option for disease-prone plants like tomatoes, peppers and cucumbers because the water goes directly to the roots. Watering only the roots means fewer weeds because they aren’t receiving irrigation. You also save water because you’re only watering what you want to grow. A drip system has flexible plastic tubing with tiny holes where you insert emitters, and you can pierce the tubing and place the emitters where you need them. A drip installation coiled around a newly planted tree is the perfect solution to giving it the deep watering it needs while its roots settle in. The biggest drawback to using a drip system is that it can be complicated to install and is more expensive than overhead or soaker systems. Furthermore, once you’ve made your holes in the tubing, you may want to make a change, and that requires plugging the hole that previously held an emitter, so you have to plan for that eventuality.

Soaker hoses allow water to seep very slowly into the ground at the roots of your plants. They’re a good solution for long, straight rows, but not ideal for a potager system with randomly spaced plants and, as soaker hoses need to be laid on level ground, they aren’t suitable for raised beds. Some I’ve talked to say they found that water was never evenly distributed in their soaker hoses, with the ends of the hose farthest from the water source never quite delivering enough moisture. Soakers also tend to last for only a few seasons.

Without knowing what your garden layout is, or your soil requirements, I suggest that, at the very least, you invest in a couple of good watering cans and the best-quality hoses you can afford. I recommend two cans because water is heavy and splitting the weight between two cans makes it easier to carry. And if possible, purchase two hoses and set them up in two zones in your garden. That way, you can attach a sprinkler and be automatically watering one section while you hand-water another. This allows you to deep-water individual plants while setting the sprinkler on low in another section. It also means you don’t have to drag the hose from one side of the garden to the other. For hand-watering with a hose, a good long-handled watering wand is also a good investment, as it enables you to reach the base of the plant rather than the foliage. The long handle also helps extend your reach into a wide garden bed without wetting foliage. Make sure to choose a wand with either a squeeze on-and-off or a twist shut-off that allows you to turn it off right at the end of the hose and not at the water source.