homesgardens

One Zone Does Not Fit All Climate Change on the Hill

by Cheryl Corson n a recent balmy evening, I lin- Nursery in Raleigh, NC, cautions that ger over the intense fragrance while the USDA Hardiness Zone map emanating from a nearby euca- is based on average winter low tem- Olyptus tree. Am I in the Berkeley Hills? peratures, it doesn’t take rare extremes No. I’m on Capitol Hill (on C Street, into account. Still, he sees the new map NE). When I first heard about this tree as a dramatic improvement due to the in 2003, I bicycled right over to see it. inclusion of a larger (30 year) tempera- And in 2012, after Snowmageddon, ture data set and many more recording several big hurricanes, an earthquake, stations. An excellent discussion of the and the fourth warmest winter on re- ins and outs of hardiness zones may be cord, it’s doing just fine. In fact, it’s found on the back page of the informa- nearly 20 feet tall. A large prickly pear tive and fun Plant Delights catalogue. cactus and a yucca plant grow in front (see: www.plantdelights.com) of it. Don’t tell the tree it shouldn’t grow here. Micro-Climate Manipulation & More Experts & Empiricists The best way to “cheat the zone” if There are scientists and then there you wish to grow plants on the margins are gardeners. While not mutually ex- of their hardiness is to create or utilize clusive, the former will say there is micro-climates. These are areas of your a difference between climate, which garden that are particularly protected, spans long time frames, and weather, receive reflected heat from a brick or which is more immediate. Garden- stone wall, or are just on the south side ers, on the other hand, will tell you of the street, out in the open. Observe that plants that couldn’t be grown here your site in various seasons and really twenty years ago without special care, learn about its light and wind exposure now do well due to warmer tempera- and drainage. Armed with this infor- tures. Both will acknowledge that ex- mation, you can usually “squeeze out an treme weather events are also becoming extra zone,” as Tony Avent says. This is more frequent. what our friends did with that eucalyp- Experts, like Dr. Catherine Woteki, tus tree. USDA Under Secretary of Research, But micro-climate only goes so far. Education and Economics, and a Hill Daniel Mullins, of the local Deep Roots resident and gardener, will point you to Landscape Company, cautions that the the newly released USDA Plant Har- increase in weather volatility as a result diness Zone Map, updated for the first of climate change will be a more salient time since 1990. This map has an online factor than mild temperature increases interactive feature that shows more de- in years to come. To cope with this vol- tail than the static maps. With it, you atility, he advises that plants which are, can see that although much of Wash- “properly planted, pruned, and mulched ington, DC is considered “Zone 7a,” are better equipped to handle extreme the next warmest “Zone 7b” now cov- weather conditions. Proper mulching ers the Potomac and Anacostia rivers, can reduce erosion and protect plants including a pocket or two on Capitol during heavy downpours as well as re- Hill. (see: http://www.planthardiness. tain soil moisture when dry conditions ars.usda.gov/) persist.” Mullins also encourages deep Tony Avent, of Plant Delights watering, which produces deeply root-

136 H HillRag | May 2012 ed plants that are much less susceptible to drought.

Celebrate the Heat We can now grow figs, ca- mellias, Chindo viburnums (a personal favorite) without win- ter protection. But there is an entire category of plants that also love our new weather (or is it climate?) – tropicals! These are plants that still need extra winter care, like being brought indoors, but can be enjoyed outdoors for more weeks of the year than in the past. Christine Moschetti, Live Goods Manager at Frager’s Hardware is just the person to see if you want to grow bou- ganvilla, tropical ginger, birds of paradise and tropical hibis- cus. She comes to DC after 28 years on Maui, and still visits her ancestral Italy every year, so she’s got a real feel for the Mediterranean climate as well. She loves tropical plants, and has even brought a mahogany tree to Frager’s Nursery as an experiment. Keith Roofing Moschetti has noticed a EXPERT WORKMANSHIP AT REASONABLE PRICES! Pennsylvania Avenue restau- rant that has already brought Residential/Commercial • Over 40 years of Experience some of its potted tropicals Chimney Repairs • Storm & Wind Damage Repair outdoors after being wintered • New or Re-Roofing over inside. She points out • Tear-Off & Replacement the difference between tropi- • Flat Roof Specialist cal and perennial (native) hi- • Copper, Tin, Sheet Metal & Rolled biscus, which can be planted • Seamless & Flat Roofs in the ground and will come back year after year. “If you’ve • Re-Sealing got the indoor space for win- • Tar, Asphalt, Gravel, Hot Coats tering them over, think of try- • Modified Bitumen ing lemons or oranges,” she Insurance Claims • Free Estimates • 24Hr. Service suggests, “their fragrance is intoxicating.” When I ask if Fully Insured • Licensed • Bonded she can imagine olive trees on “No Job Too Large or Small” Capitol Hill, she laughs and Senior & Military Discounts Available! says, “maybe not yet, but who knows?!” 202-486-7359 Cheryl Corson (www.cherylcorson. All Work Inspected by Owner...Deals Directly with Customers! com) is a landscape architect who has H worked on the Hill since 1998. All Work Fully Guaranteed capitalcommunitynews.com H 137