Gardening for the Climate

Carbon is constantly cycling from the air into plants and soil, and back into air. Global warming is largely a result of an imbalance in this carbon cycle, due to the release of vast quantities of ancient carbon that have been burned as fossil fuel. CO2 and other heat trapping gases act as a blanket, trapping heat and altering weather patterns around the world.

Summers are getting hotter and winters generally not as cold. This means that hardiness zones are shifting, making planning your garden more challenging. Climate change is also projected to increase the frequency and severity of extreme weather and to benefit some pests and weeds. (e.g. poison ivy)

Gardeners can do more than simply try to adapt to the changes—they can make choices in their gardens that don’t add to the problem. The following are 5 steps that you can take.

Step 1: Minimize Carbon-Emitting Inputs − The kinds of tools and chemicals you use can affect the amount of heat-trapping gasses your garden absorbs or emits. Gasoline-powered tools are obvious CO2 emitters. but the synthetic fertilizers and pesticides require large amounts of energy to manufacture and consequently are responsible for significant amounts CO2 emission. Herbicides are the highest generators of carbon emissions among pesticides, and glyphosate (Roundup) is among the most carbon-intensive of the herbicides.

Step 2: Don’t Leave Garden Soil Naked − Bare soil is vulnerable to erosion, weeds and carbon loss. Use cover crops whenever possible to protect and build your soil during the winter and other non- growing months.

Step 3: Plant Trees and Shrubs − All plants absorb CO2 through their leaves, storing the carbon in their tissues. But trees and shrubs because they are large, woody and long-lived can store larger quantities of carbon than other plants, for longer periods of time. Urban and suburban trees can also prevent CO2 emissions because they can shade building in the summer and buffer them from cold winter winds, reducing the need for cooling and heating.

Step 4: Expand Recycling in the Garden − Landfills produce methane gas which is 23 times more potent than CO2. Help reduce the growth of landfills by turning leaves, grass, woody clippings, dead plants and non-meat or dairy kitchen waste into mulch or compost. Composting takes place in the presence of oxygen, minimizing the production of methane.

Step 5: Think Long and Hard About Your Lawn − Reduce the size of your lawn and then minimize watering, fertilize carefully and leave grass clippings on the lawn, mow high and choose the right grass.

As a gardener you can lead the way in your own landscape.

Condensed from the Climate-Friendly Gardener, Union of Concerned Scientists, http://www.ucsusa.org/food_and_agriculture/what_you_can_do/the-climate-friendly-gardener.html

Carol Ivory, Loudoun County Master Gardener