American obsessions come and go, but one that has held our interest for a very long time is lawns.
Approximately 50 million acres are planted in turf, with only a very small percentage being golf courses, parks and public spaces. The majority of that number is almost entirely residential acres.
Lawns have surpassed corn to become the nation’s No.1 irrigated crop. According to the EPA, we consume 26 billion gallons of water daily, and 30% of that daily total is for outdoor use, mainly to irrigate our lawns.
In addition to water, we also apply 80 million pounds of pesticides to our lawns and use 1.2 billion gallons of gasoline in our mowers, spilling 17 million of that in the process as we refuel, more than was spilled in the Exxon Valdez tanker accident of 1989. On top of that, the average lawn mower creates as much pollution in one hour as do 11 cars driven for the same amount of time.
Americans are not about to give up their lawns. However, some changes can make our lawns kinder to our environment and natural resources.
The simplest is to just reduce the size of our lawns, perhaps replacing some of that space with a mix of native trees, shrubs and perennials that are more beneficial to pollinators and other wildlife.
We can also quit applying as much herbicide in our quest for the perfect lawn, especially since not all “weeds” are bad. Advertising leads us to believe that dandelions are the worst thing ever, when actually they are a great food source for pollinators. And that white clover we are told to eliminate actually pulls nitrogen from the air and puts it in the soil, fertilizing in the process.
When shopping for fertilizer, look for organic slow release formulas, or use compost. You also want to make sure fertilizer is only applied at the right time of year, and only in the recommended amounts.
Turfgrass falls into two basic types, warm season and cool season, and both differ as to when you fertilize and how much you need to water. In coastal Virginia the more environmentally friendly choices are warm season grasses like Bermuda, St. Augustine, zoysia and centipede. Once established they are all very well-adapted to our heat and humidity and require less water. They also knit together thickly enough to keep most weeds from establishing. The drawback for most homeowners is that they are not green in the winter, but they can be over-seeded with winter rye.
Fescue, on the other hand, is a cool season grass, which does stay green in the winter, but requires copious amounts of water to do well in our summers.
No matter what type of grass you have, it will be healthier if you allow it to grow a little taller before cutting, about 3 inches. Also, make sure your mower blade is kept sharp; a ragged cut from a dull blade will make the grass lose moisture quicker. When you do have to water your lawn, do so in the morning so the grass has a chance to dry before night. Wet grass at night can lead to fungus. It is also better to have less frequent but longer periods of watering to promote deep, healthy roots.
Les Parks is the Director of Horticulture at Norfolk Botanical Garden.
Wild Green Yonder is a recurring monthly feature from the staff of the Norfolk Botanical Garden.
