Designing sustainable garden is all the rage, and a trend that is here to stay. But what does it mean? Sustainability is a complete mindset change – a lifestyle shift where homeowners seek to create and maintain their gardens in ways that will not negatively impact the earth for future generations. The primary goal is to “first do no harm” – avoid practices that will damage the environment, and focus on methods that mimic nature and conserve natural resources. It sounds complicated but is actually fairly easy to learn, and once you have established a sustainable landscape, it will save you money, time, and effort.
To learn more about designing a sustainable garden, I interviewed Susan M. Varlamoff, author of “Sustainable Gardening for the Southeast.” Susan recently retired as director of the Office of Environmental Sciences at the University of Georgia. Her book is a great resource for those who want gardens that are easier to maintain and more eco-friendly. “We gardeners can be an ecological force for good as we garden,” Susan remarks. “We can either benefit the environment or we can harm the environment. It really is not that difficult.”
Here are Susan’s top tips for creating a sustainable garden…
Cultivate a healthy soil – It really is all about the dirt! According to Susan, “Soil in the Southeast is typically clay or sand and needs generous amounts of compost to make it fertile and suitable to grow a lush garden.” She suggests first bringing a soil sample to your local extension office for analysis to determine what nutrients need to be added. Then start a compost pile or bin. Compost is decomposed organic matter (humus) that increases soil fertility. It is “black gold” and free when you do it yourself. Just start a pile of grass clippings, chopped leaves, sawdust, twigs, vegetable peelings, coffee grounds, tea bags and wood ash; turn the pile occasionally, and watch nature change your yard waste into beautiful compost for your garden! Top dress your garden beds with organic mulch like wood chips, pine straw or pine bark. Over time the mulch will decompose and add more organic matter to the soil.
Plant trees – Susan calls trees the “ecological powerhouses” that absorb carbon dioxide and give off life-sustaining oxygen. According to research, one tree can remove 26 pounds of carbon dioxide from the atmosphere annually, equaling 11,000 miles of car emissions! Trees help prevent erosion, cool the earth, collect and filter storm water, improve the air and support the needs of wildlife. If you do one “sustainable” thing, Susan suggests you plant a native oak tree (Quercus). According to research, our mighty native oaks support the needs of more wildlife than any other tree.
Restore biodiversity with native plants – A healthy landscape is a diverse landscape with a variety of plants that attract birds, pollinators and other beneficial insects. If you plant only non-native plants, you are creating an ecological “dead zone” that native wildlife does not recognize. While many of our favorite plants that were introduced from Asia and other locales are lovely and not harmful, they do not have the same advantages as native plants. Our natives are adapted specifically to our climate and can handle more readily severe weather changes, such as drought. Native insects and birds look for specific native plants and find most non-native plants unappetizing. You don’t need to give up your azaleas, gardenias and camellias, but should aim to add some diversity with tried-and-true natives like oak leaf hydrangea (Hydrangea quercifolia), American beautyberry (Callicarpa Americana), bottlebrush buckeye (Aesculus parviflora), or Virginia sweetspire (Itea virginica).
Reduce lawn size – Homeowners love their lawns. Turf grass provides a wonderful service by absorbing air pollutants, lowering air temperature in the summer, cutting noise levels, filtering storm water and providing a place for kids to run and play. Many homeowners, however, see the lawn as their major and largest landscape feature and tend to over-water, over-fertilize and overuse pesticides on the lawn, resulting in run-off into storm drains, polluting our rivers and streams. UGA experts suggest that the lawn be no larger than 40% of the entire landscape. Re-think your lawn size and see if another ground cover or mulch might make more sense. A sustainable gardener will learn to tolerate a few weeds, insects and diseases to avoid the over-use of pesticides that damage wildlife and the environment. “I only water my lawn when it shows distress,” Susan says. “I don’t sweat weeds and I use an organic lawn service.”
Water wisely – Conserving water is paramount in a sustainable garden, and a good plan starts with grouping plants according to water needs. About 60% of your garden should be filled with plants that survive on just rainfall and require little or no supplemental watering, except in extreme drought. Examples of plants with low-watering needs include established native trees and shrubs. 30% of your landscape can contain plants with medium-watering requirements – those that need supplemental watering after a couple weeks without rain. Perennial beds and lawns are examples of medium water users. 10% or less of plants should be in the high-watering category. These include annuals or tropical plants. Place them as focal points for visual impact.
Other water-wise tips include: water plants in the early morning or late evening to prevent evaporation; use a rain gauge to measure precipitation; add rain barrels to downspouts to collect rainfall for watering, and mulch beds to retain moisture.
Manage pests naturally – “Nature will take care of pests if you plant a diverse landscape that supports beneficial insects and birds,” Susan points out. “If I have a plant that is a pest magnet, I take it out. There is no point in fussing with infestations and really no reason to use pesticides.”
For more information on sustainable gardening and to purchase Susan M. Varlamoff’s book, “Sustainable Gardening for the Southeast,” go to University Press of Florida, order from Amazon.com or find it at your local bookstore.