Warming up to the heat-zone map

The USDA map, although enormously popular and widely used, has its limitations. For example, Zone 7 in Maryland is a world away from Zone 7 in Oregon, or north Texas, or the foothills of California’s Sierra Nevada mountains. In many parts of the country, heat rather than cold dictates which plants are able to survive from one year to the next.

Thus, in 1997 (after years of study and research), the American Horticultural Society released its own map, the AHS Heat-Zone Map. Though still relatively new and still being tweaked, this map has proven quite useful to gardeners in the South and West. You can download the Heat-Zone Map at www.ahs.org/ publications/heat_zone_map.htm.

The AHS map has 12 zones. Relatively cooler Zone 1 is defined as having only one day of 86°F weather per year; sweltering Zone 12 has 210 days of such heat or more.
Research has shown that 86°F is the temperature at which many plants —that is, their cells, or plant tissue — start to experience damage from heat. That’s why that point became the baseline for laying out the heat zones. U.S. gardeners in areas where the main source of plant stress is not winter cold but summer heat prefer this system. Nurseries in hot areas are starting to refer to these zones more and more. If the heat-zone information isn’t supplied for a plant you’re interested in, look in newer regional reference books and plant catalogs and Web sites.

Taking a look at the world’s plant hardiness zone maps

Every part of the world has its own hardiness zones, and most maps are set up the same way. The USDA Plant Hardiness Zone Map, for example, is a color-coded or shaded map, sometimes accompanied by a chart that expresses the same information. This book displays the map in the color section, and you can also see the map (and others) in many places after you become tuned in to it — a poster tacked up on the wall at your local garden center, the back flyleaf of gardening books, in the back pages of most garden magazines, or tucked into the interior of your favorite gardening catalog.

You can also access it online at www.usna.usda.gov/Hardzone/ushzmap. The United States Department of Agriculture published, and has occasionally modified and updated, this hardiness zone map of North America. The most recent map, based on climate data gathered at National Weather Service stations throughout the U.S. and by weather stations throughout Canada and Mexico, came out in 1990. You can find 11 zones marking the average lowest winter temperatures, with Zones 2–10 divided into subzones. Canada’s plant hardiness zone map, suited for Canada’s colder climate, shows nine zones, based on average climatic conditions and altitude of each area. The harshest zone is 0, and the mildest is 8. In addition, the major zones are further divided into subzones. For example, Zone 4 splits into 4a and 4b, where zone a is slightly colder than zone b. You can see Canada’s map at atlas.nrcan. gc.ca/site/english/maps/environment/land/planthardi.

The Hardiness Zone Map of Europe presents a general overview of the European continent and can be broken down further into each European nation and the zones within it. You can see this map online at www.uk. gardenweb.com/forums/zones/hze.

China’s plant hardiness zone map covers arguably largest and most varied gardening spots in the world. You can view it at www.backyardgardener. com/zone/china.

Plant hardiness zone maps aren’t limited to just the Northern Hemisphere of the Earth! You can find online maps for South America and Africa as well. And the Australian government has established a series of maps that many Australian gardeners use to gauge not only planting zones and climates but also rainfall. To view the plant hardiness zone map of Australia, go to www. anbg.gov.au/hort.research/zones. To see Australia’s climate zone maps, visit www.bom.gov.au/climate/austmaps. Traveler beware: If you buy a plant marked as perennial or hardy in the deep Southern USA or California and you live in a chilly northern region, the plant may be labeled such only for the area where it’s sold.

Different Hardiness Zone Maps for Different Folks

If all that gardeners ever grew were locally adapted plants, you’d have no reason to find out or concern yourself with hardiness zones. But of course, you want it all, right? You want to grow exotic goodies from distant lands or plants from allegedly similar but far-off places.
Indeed, you already do have it all: Peonies come from Asia, tulips hail from Turkey, and strawflowers are from Australia. So after your initial infatuation with a plant that’s new to you, you can ask yourself, “Is growing this in my garden possible?” Finding out the plant’s appropriate zone gives you an answer.

People commonly use hardiness-zone information for trees, shrubs, and perennial plants. Annuals don’t get rated, or just don’t count, because they live for only one growing season, anyway. Hardiness zones are all about survival from one year to the next. (And anything tender grown in a pot can always be moved inside out of the weather, thus avoiding the issue.) Just to complicate matters, different zone maps are out there, and some are better depending on where you live.

The USDA Plant Hardiness Zone Map is the most prevalent one that gardeners in North America use, but others exist. The American Horticultural Society’s Heat-Zone Map is more useful and popular for people in the Southern and Western USA, while Sunset’s Garden Climate Zones Map, though complex, serves the Western states well.

Who is Master Gardeners?

A master gardener isn’t someone you hire but rather someone you can consult and consider a resource. Master gardeners have to follow a certification process. Throughout the country at Cooperative Extension Service offices (staffing and budgeting permitting, I should add), classes train avid home gardeners or anyone else who’s interested in horticulture.

Candidates take a core course, often in the fall or winter when life outdoors is less busy. Certification follows only after the student has completed additional classes and a certain number of hours volunteering in the community. The volunteering can involve anything from manning the phone help line to assisting with community plantings (including school gardens), working with 4-H, holding plant clinics at garden centers, staffing county and state fair booths, assisting with horticulture therapy projects, or helping with workshops that educate the public about gardening.
The hours and courses required for certification varies from office to office, state to state. Getting certified doesn’t make a person an expert; it just shows that he or she has made a commitment to learning more about and serving in the local horticultural scene.

Master gardeners aren’t paid, so you can’t really haul them over to your yard and get them to do your work for you. However, they can help you with questions and point you toward helpful resources. And who knows? In time, you may decide to become one yourself.
To find a master gardener, call the nearest office of the Cooperative Extension Service. You can also run an Internet search or go to www.ahs.org/master_gardeners/index.htm.

Who are landscape or general contractors?

Landscape or general contractors are the folks who are usually called in to actually install the job. They do the heavy lifting.

If you’re daring (or foolish), maybe you’ll try to take down a massive shade tree or regrade a slope or install an in-ground irrigation system or lay out and install a flagstone terrace. Before taking this step, think whether the money you’re saving will be enough to pay for the chiropractor you may need afterwards! But seriously, if you’re not used to this work, you can do a lot of damage to you and your landscape. Don’t be afraid to ask someone for help to create your vision: somebody strong enough, experienced, and knowledgeable; somebody certified, bonded, and insured as well. A reputable contractor has no problem demonstrating his or her qualifications. Getting help isn’t wimpy; it’s only good sense.

In short, let someone else do the hard jobs and do them safely and correctly the first time. These folks can install all your residential hardscape needs like walks and walls. Save the fun and creative parts for yourself. To find a landscape or general contractor, check the yellow pages; ask neighbors; ask at a garden center; check ads in the local newspaper; or copy the number or Web site off a truck parked at another home.

Understanding Landscape architects, landscape designers, and garden designers

Landscapes versus gardens, architects versus designers — confusing isn’t it? Various names apply to this group of professionals. Although they each perform a service, you may find quite bit of overlap.

Landscape architects, landscape designers, and garden designers are all professionals, trained in every facet of planning and realizing an outdoor plan. Their scope goes beyond regular backyard gardens or even the landscaping of an estate; many of these folks are capable of laying out a resort, college campus, public park, and so on. They can cope with topography and know how to analyze a site completely, down to its soil and light and existing vegetation. They can design walkways and decks and such in savvy and attractive ways. They can then draw up a design or several alternatives. In general, landscape architects are space planners who may or may not be very knowledgeable about plants. They’re mostly called in for very large commercial or institutional projects and where hardscapes (any masonry or woodwork like walks, patios, gazebos) are a substantial part of the job. You may find that landscape designers and garden designers are more familiar with plants suited to your area and may be more attuned to residential scale projects.

All concerns about cost aside, hiring someone like this to do your yard is a marvelous investment. These professionals tend to notice and address elements and problems you may not have thought of; they propose appropriate and attractive solutions; and they have wide knowledge of both plant material and hardscape components. They’re the full planning package. To find one of these experts, you can consult ads, the Internet, or the yellow pages. Word of mouth may work. If you know of someone who’s used one in your neighborhood or town, try to visit and ask the owners how the process went, whether they’re happy, and perhaps — if asking doesn’t seem too tacky — what it all cost. Garden tours in your area may feature professionally done properties, too, which can also lead you to the person who designed a beautiful garden.

How to Get Professional Help for Your Garden Plans?

Getting a garden plot ready, especially a large one, isn’t easy, and I don’t pretend that it is (I have better uses for my creative energy, such as pretending I’m in Hawaii). If starting the process makes your head reel, or if you don’t have confidence in your design sense, don’t worry. Others can do it for you. They can do everything, in fact, from planning on paper to purchasing to digging the holes and planting the plants. You can confer with or hover over them, or wind them up and let them go. You can even stop them at the point where you want to take over.

Also, be honest with yourself when a project is beyond your ability, unsafe for you, or too time-consuming to undertake on your own. Under such circumstances, go ahead and hire a contractor.
If you decided to get professional landscaping help, be savvy so you get good work and you get what you pay for. Here are some guidelines:

• Before you check the yellow pages, ask around. Word-of-mouth is an ideal way to get started.
• Find a minimum of three possible contractors. They should be willing to make an initial appointment that involves assessing and estimating only; be sure to ask whether they charge for this step (and whether, if you go with them, the fee can be credited to the job).
• When the professionals arrive, have some copies of your plans to show and, if need be, hand them over.
• Ask for a bid in writing. Materials and labor estimates. With a clause for addressing unexpected expenses and overruns. To figure out what a reasonable cost would be, ask friends and neighbors what they paid, and get estimates from multiple sources.
• Check references. Also confirm that the contractor is both licensed and insured.
• Pick someone you like and, more importantly, can communicate with. _ Discuss concerns every step of the way — the more communication, the better. If changes come up, be smart and get the revised plans and charges in writing.
• Pay in installments — give a deposit, then perhaps pay a second installment or more, and finally pay the last one when all parties agree the work is complete and satisfactory. Such an arrangement gives the contractor security and a commitment from you but also prevents you from being taken for a large fee if something goes awry.

Overall, just be clear with one another. Have a budget. Get written estimates. Get your agreement (plan, expectations, and timetable) in writing. Call or visit references. Check and/or supervise the work.

Start the process of hiring a contractor early if you can. Winter is an ideal time. Good people have full calendars, and spring commitments are booked very early. Finding the right professional, somebody you can afford, or someone nearby may take some time; you may interview several before settling on one.