After what seemed a very long winter, we’ve had an erratic and very dry spring here in Minnesota.
For the fifth year in a row our May, a normally wet month, was dry. Less than a half inch of rain fell this May, with only two other May’s on record having had less. This is hard on young plants trying to get a start on the season. Luckily it has been cool. The windier conditions we’ve had are drying enough without adding heat to the equation.
The forecast is calling for a chance of rain everyday over the next several days. I hope we get some everyday, the ponds and lakes are low. We are down about three inches on the year, and last year we were down eight inches.
What can we do? Reduce the size of our lawns, and reduce the affect the sun has on drying the earth by planting trees and shrubs.
Should we water our lawns? Yes, but when it is really dry, we need to think of saving trees and shrubs, too, if not first.
The failure of the neighbor across the street to water will be costly.
Water is a precious resource, and we don’t want to waste it. Many people think watering trees and lawns is a waste. However, not watering will invite weeds, which have to be dealt with through labor and/or herbicides that may be damaging to the environment. Trees, shrubs and plants have greater value than grass, except in native grasslands–the prairie. The time invested in a tree is valuable, too. Lose one, and it takes years to replace, plus the plant life that has adapted to living beneath the canopy also suffers. Replacing trees, plants, and lawns is costly, so avoid it by taking care of the plants you have.
Nature abhors a void, and will fill it with a plant or two not wanted in that spot, the true definition of a weed. Healthy lawns keep weeds out. A lawn that is drying up and dying, and even a lawn getting thin, invites weeds. Herbicides are expensive and generally aren’t healthy for life in general, but it’s how most people deal with weeds. So, be good to the environment, your pocketbook, and to your lawn and other plants by watering smart.
Smart Watering means Watering Deep
The roots of most plants– trees, shrubs and grasses, serve three purposes: to (1) hold the plant in place so it can (2) feed and (3) drink, with the goal of growing and reproducing. The entire root system holds the plant in place, while specialized parts of the roots absorb nutrients and water necessary for life. Feeder roots are near the surface and extend beyond the drip line. They are close to the surface because that’s where most of the nutrients are located. Water is required for feeding. An unwatered plant won’t get any nutrients and will die. Many plants have tap roots, too, which are designed specifically for obtaining life-sustaining water from deep in the ground.
In drought conditions and really hot weather, it is important to get the water deep under the surface. Water on and close to the surface of the ground easily evaporates. When water gets a few inches below the surface the soil retains the moisture, which is often measured by agronomists, and is called sub-soil moisture.
Watering deep encourages grasses and other plants to send their roots down deep. Lightly watering causes more harm than good. Unless one waters deeply the plant doesn’t use its energy to send its roots down. It concentrates its efforts in that first inch or two of soil when it is lightly watered, say with an automatically sprinkling system every few days. When drought hits, or unusually high temperatures occur for several days, these shallowly watered and rooted plants are the first to dry up and die. Their tap roots weren’t fully developed, and thus can’t reach sufficient sub-soil moisture beneath the top soil in cooler, insulated earth. (This is where mulch comes in.)
In the spring, water deeply when there have been reports of low sub-soil moisture, and before high temperatures or drought can occur. This provides several benefits. The most important is it will save your plants, but it also means won’t have to water as often. A lesser percentage of water will be lost to evaporation with more going to the plant. Less water will be used overall, because watering deep is more efficient.
I recommend watering in the early morning before the wind normally picks up, and the leaves can dry to avoid fungus and other issues.
What is Watering Deep?
Watering deeply means putting down at least an inch of water, maybe two. If you are using a sprinkler system, you can gauge how much water is going down by putting a pot saucer (one at least an inch deep) out in the path of your sprinkler. If you are hose watering large plants and trees, water until it puddles around the plant, go to another plant, then return to the first plant and water until it puddles around the plant again, draining more slowing. Showering a plant will put the water on the drip line, and once identified if the leaves aren’t touching the soil, water a few inches either side of the drip line and toward the center if the plant is known to have a deep tap root.
In the heat of the summer, thirsty plants like roses, and grasses kept short, need about an inch a week to flourish, but most other common plants require less. To protect the earth and your lawn as higher temperatures arrive, or if little or no rain is in the forecast, set your lawnmower up a notch or two. While I don’t scalp my lawn in the spring, if we are getting good rainfall I will keep it very short while it is still cool to encourage rhizome growth for a healthy, thick lawn that will prevent weeds from getting a foothold. Then I increase the height of my mower a setting every 10° (F) increase in temperature.
One last thought on watering smart, efficiently and effectively. Know your plants so you can properly site and care for your plants. BTW. I didn’t finish this last night, and this morning it is starting to rain.