The cool sensation of walking barefoot through the grass is very real. Temperatures on lawn surfaces can be 10 to 14 degrees cooler than on concrete or asphalt. Green spaces can play a big role in modifying temperatures and controlling climate.
Through photosynthesis grass absorbs sunlight to produce energy. Grass plants will take in the Sun's heat during the day and release it slowly at night, helping to moderate temperatures.
Turf helps cool off surrounding areas through the evapotranspiration process. Lawn areas cool the air as water evaporates from the blades of grass. As much as 50% of the Sun's heat falling on the turf will be absorbed and eliminated through transpiration.
The front lawns of eight homes can have the cooling effect of 70 tons of air conditioning, greatly reducing energy needs and the burning of fossil fuels needed to produce it. It has been estimated that strategic planting of lawns and landscape plants could reduce the energy required for air conditioning by 25%.
Green spaces are very important in helping to control hot Summer temperatures, especially in urban areas. Overall temperatures in urban areas have been found to be 5 to 7 degrees warmer than in rural areas. A study by the University of Manchester has found that a 10% increase in green space in urban areas would reduce urban surface temperatures by up to 4 degrees. This would have a major impact on countering the "heat island" effect so common in large urban areas.
Subsequent mowing should be done whenever the grass clippings measure 1/2" or 25% of the above ground grass plant. Never cut off more than one third of the plant height (approximately 3/4") at any one mowing. Removal of too much of the plant may result in shock, unsightly appearance, or susceptibility to disease.
Our lawns and plants help to cool the environment. It is cool to be green.
- The Lawn Institute
- University of Minnesota