Tips for growing a more resource-efficient lawn
By SKIP RICHTER
Water supplies are not unlimited, and lawns are often vilified for their “drinking problem.” Much of the water applied to lawns is wasted because of misapplication, incorrect scheduling and systems in disrepair.
Turfgrass loves the sun but uses less water in bright shade. Areas too shady for a lawn can be converted to an attractive shade garden with mulched areas between plants or a shady outdoor sitting area with mulch or pavestones to allow rainfall to percolate into the soil while providing an all-weather surface.
There seems to be a love-hate relationship with the American lawn. On the one hand, the expanse of turfgrass provides a verdant outdoor carpet on which kids, pets and adults alike can play, as well as an outdoor social setting for gatherings of friends and family.
On the other hand, significant time and resources go into keeping our lawns in pristine shape. Weekly mowing and watering, periodic fertilizing and managing pests, diseases and weeds costs us both time and money.
Then there are the environmental factors. Lawns absorb rainfall, reducing runoff and soil erosion. Turf captures the summer sun and moderates temperatures. On the other hand, fertilizers and pesticides that are misapplied or applied in excessive amounts can contaminate surface and groundwater supplies.
Water supplies are not unlimited, and lawns are often vilified for their “drinking problem.” I will point out, however, that people rather than turf bear at least equal blame, because much of the water applied to lawns is wasted because of misapplication, incorrect scheduling and systems in disrepair.
I would rather not enter the “turf wars” debate in this column, so any lawn rangers and turf despisers can holster their weapons and relax. The reality is that the vast majority of people with property around their home have a lawn, and lawns to one degree or another are here to stay. So, what can we do to keep our lawn as resource efficient and environmentally positive as possible?
First of all, it would be helpful to evaluate the size and location of our turf areas. If you have a large expanse of turf in areas where is it not used, it would be worth thinking through whether the supplemental watering is worth the cost. Reducing turf to where you really use it most can go a long way toward conserving water and the monthly expense.
Turfgrass loves the sun but uses less water in bright shade. Areas too shady for a lawn can be converted to an attractive shade garden with mulched areas between plants or a shady outdoor sitting area with mulch or pavestones to allow rainfall to percolate into the soil while providing an all-weather surface.
Where you have bright shade or part-day sun, a lawn may make sense because there is enough light to sustain it but some shade to lower its water needs. Our area receives considerable rainfall — enough that a lawn in a bright shady area can survive with a fraction of the supplemental irrigation most lawns receive.
Second, there is a right and a wrong way to water. Frequent light irrigation predisposes a lawn to diseases, promotes shallow rooting and even wastes water. Here’s why: Most diseases thrive in wet conditions on plant leaves, roots or stems. Therefore, watering less often can help decrease the incidence and severity of some turfgrass diseases.
Turfgrass, like most other plants, will grow roots where there is moist soil. Frequent, light irrigation results in the soil only being wet near the surface, promoting shallow rooting. A deep soaking on an infrequent basis provides the moisture and oxygen down in the soil that encourages deeper rooting.
Frequent light watering wets the leaves, thatch and soil surface, but not much more. After the irrigation cycle all the water on the leaves, thatch and even some from the soil surface is lost to evaporation. This is not a very water-efficient way to use your municipal drinking water.
On the other hand, with a more thorough soaking, after the leaves, thatch and surface are wet, the rest of the water soaks down into the soil, where it will stay in the soil’s “bank account,” available for future withdrawals by your turfgrass. Therefore, for example, you get more efficient use of your water when you apply 1 inch of irrigation in a series of cycle and soak applications once a week or so, than making three applications of ⅓ inch spaced out over the same period. Keep in mind that sandy soils hold less water than clay soils and will need comparatively more frequent watering.
Fertilize your lawn enough to keep the turfgrass healthy but not so much as to push excessive growth. Excessive fertilizer applications result in more mowing and a shallower-rooted, problem-prone, drought-sensitive grass plant and an increased likelihood that the excess nutrients end up in local waterways. When applying pesticide or fertilizer, always take care to direct it onto the lawn and prevent it from landing on driveways or sidewalks, where it will be washed away with the next rain. After applications, use a broom or blower to move any that landed on hard surfaces back onto the lawn.
The bottom line is that with sound lawn care practices you can significantly reduce any negative impacts of a lawn while enjoying the positive benefits.