As someone who likes to try and keep my word, I am disturbed by the possibility of the Trump administration rolling back some of the environmental standards set by the Obama administration. My first thought was to plan a Million Car March on Washington, with lines of cars clogging the street in front of 1600 Pennsylvania Avenue, as drivers outfitted with oxygen tanks idled their engines to remind the administration what some of America’s cities once considered to be “fresh air.” Maybe Volkswagen would come in as a sponsor and provide a few thousand of their diesel cars to be added into the mix, to make the point of why we have regulations in the first place (and why we need to enforce to them).
I still like this idea but, while I feel that protest and making a statement is important, just as important is doing what we can as individuals to help fight global warming. As a gardener, I am determined to use my plantings and garden design to minimize my own energy consumption, and I hope others will do the same. I have the good fortune to have a house sited in a manner that allows me to use carefully placed plantings to my advantage throughout the seasons. And as I renovate the house and garden, I hope to cut my energy consumption through intelligent design.
My house, a pole barn built in the eighties, has something in common with my old house in Connecticut: Both houses have a long southern exposure filled with windows. These designs allow the low winter light in to warm the stone and concrete floors on the first level of each house. Then, as the sun moves through the seasons and comes to sit directly overhead by summer, the sunlight that comes in is indirect. The floors do not soak up summer heat and therefore do not radiate warmth in the evening, sparing me unpleasantly warm, sleepless nights. As a matter of fact, in summer the cool concrete floors of my current house help to mitigate the summer heat and keep my dog Fred and me comfortable on all but the hottest of days. (Being smarter than I am, Fred suns himself on the concrete in winter and cools down on it in summer). And my current house has another great advantage: an almost windowless northern exposure that helps prevent the cold northerly winter winds from infiltrating the house in the depths of January and February.
These factors can help cut energy usage significantly, but there are other things we can do to retain heat in the winter and keep our houses cooler in the summer. Our forbears understood many of these, and I hope to utilize them as well. Farmers have long understood the importance of windbreaks in protecting crops and houses from exposure to cold winter winds. And, as I devise a plan for my northern, windowless street front, I know that an evergreen windbreak will protect me from northwesterly winds.
Thirty years ago, my friends who built the house in which I now live planted a cedar hedge about 40 feet from the house that helped to minimize the impact of winter winds. When I moved in, it was overgrown and weak. I took it down this winter (and know that as part of my personal cap-and-trade program I need to replant it to make up for the emissions from my gas powered chainsaw). I plan on rebuilding the hedge with a mix of evergreen natives, perhaps salt-tolerant bayberry and Canadian hemlocks, along with a few of the remaining Eastern cedars and pines. The best windbreaks provide protection from more than just one direction (mine will shelter me from the north and the west), are sited at a distance of about two to four times their height away from the house, block wind both low to the ground and higher up, and allow some air to pass through (unlike a fence) to prevent causing a vacuum effect which will draw the cold air up and back down and against the house.
Planting taller conifers and evergreen shrubs to the windward or upwind side, and a lower collection of shrubs (both deciduous and evergreen selections) to the leeward or protected side, will further minimize this vacuum effect. For maximum effect, the plantings should be dense when they mature. I hope to include a few rhododendrons, oakleaf hydrangeas, yellow-twigged dogwoods, and fringetrees as part of this mix, which can provide the area with seasonal interest while creating a habitat for wildlife as well. Such windbreaks can save up to 25 to 40 percent on energy consumption for heating, according to a recent study in South Dakota.
While these savings will be invested in the plantings in the first few seasons, after that the energy cost reductions can be a part of my plant budget for the rest of the garden, which will include some plantings that will help to manage summer sun. What better form of green energy and investment could I imagine?
I suppose I could invest the savings in fuel for the Million Car March, but perhaps I will just buy an electric chainsaw and add solar panels to my roof and focus on my own personal cap-and-trade system. Maybe I am an isolationist, too.
A gardener grows through observation, experimentation, and learning from the failures, triumphs, and hard work of oneself and others. In this sense, all gardeners are self-taught, while at the same time intrinsically connected to a tradition and a community that finds satisfaction through working the soil and sharing their experiences with one another. This column explores those relationships and how we learn about the world around us from plants and our fellow gardeners.