The gardening season never ends when you have a greenhouse: There's always something growing on.

Greenhouses give cold-climate gardeners the luxury of keeping their fingers in the dirt through the winter, and warm-climate gardeners a chance to experiment with truly tropical plants year-round. In any climate, a greenhouse is the perfect place to get ahead of the calendar and start seeds and tend to transplants. In a greenhouse, in the dead of winter, lemon blossoms perfume the air, basil and other tender herbs flourish, seedlings push happily up into the light and warmth. Not surprisingly, gardeners thrive in a greenhouse environment, too.

"A lot of people just want to sit among their plants and do nothing, just enjoy it," says Shelley Newman, vice president of Hartley Botanic, which has been making greenhouses in England since 1938.

Plant collectors used to be the main customers for greenhouses, says Charley Yaw, owner of Charley's Greenhouse & Garden in Mount Vernon, Wash. Orchids, tender cacti and fancy flowers filled the shelves in these elaborate structures. Now, a large new generation of gardeners interested in starting seeds early and vegetable gardening in the offseason is making room in its backyards for hard-working greenhouses.

"There are a ton more greenhouses being sold today than 20 years ago," Yaw says. "And it doesn't take a real expensive or sophisticated greenhouse to grow vegetables."

Greenhouses can be just about any size, but the experts generally recommend a greenhouse with a footprint of about 8 by 10 feet. Yaw's formula for customers is easy: "Figure out what you want, then add 50 percent," he says. If two people will be working in the greenhouse together, a 10-by-12-foot space allows more elbow room, Yaw says, and more growing space, too. Newman recommends an even larger size for real enthusiasts; Hartley Botanic's most popular greenhouse size is 11 by 20 feet. "I'll tell you this," she says. "Everybody underbuys."

Building restrictions and setback limits may influence your decision, so it's a good idea to check on local zoning regulations before you get started. Temporary structures may not be regulated. Barbara Damrosch and Eliot Coleman, owners of Four Season Farm in Maine, rely on temporary 10-by-12-foot hoop-top greenhouses placed right on top of the soil to extend the seasons in their vegetable gardens.

Putting up a permanent greenhouse requires a bit of planning. You want it to look nice in your garden. You'll have to consider the layout of your property and the relationship of the greenhouse to the rest of the garden and your home. It should be on the south side of your house to take best advantage of the light, and away from screening evergreen trees.

A path through the middle should be paved solidly, to avoid muddy feet; gravel or pavers under the growing benches also help keep the greenhouse tidy. It's practical to have a patio or pad of pavers, bricks or stone outside the greenhouse door; this area can also be used as a staging area for plants making the transition from the greenhouse to the garden.

Hartley Botanic's greenhouses have glass panels, but not all greenhouses use glass. Plastic polycarbonate panels are popular, Yaw says, and the material is especially good insulation. Polycarbonate also diffuses the light, so plants do not get burned in bright sun.

Depending on where you live, an electric or gas heating system may be necessary, although passive heat will suffice on many days. Fans and automatic vents help prevent overheating.

Donna Clark, a retired garden designer in Greensboro, N.C., had a modest, hardworking greenhouse on the back of her two-car garage when she lived in Connecticut. When she and her husband sold their house and moved south, her dream of a Hartley Botanic greenhouse came true. Her Victorian-style greenhouse is just 11 by 10 feet, with a gravel floor. Shelves for plants line the sides, and a potting bench fits neatly against the back wall. "Some people want a fancy car," she says. "I wanted a fancy greenhouse."

Clark grows annual flowers from seed in her greenhouse, nurturing the tiny plants before transplanting them into the garden; she also starts seeds for her extensive vegetable garden. Last year, she grew cucumbers in the greenhouse, and harvested them long before cucumbers could have been produced in the garden outdoors. This winter, she is using her greenhouse as a studio experimenting with mosaics.

Greenhouses are not an impulse purchase. Inexpensive do-it-yourself models start at about $500 and run up to about $2,000. Larger greenhouses with more features are substantial structures and cost $5,000 or more. Hartley Botanic's fancy Victorian greenhouse is quite an investment, at $45,000 to $50,000.

The winter months are the perfect time to be considering a greenhouse. Some models are on sale, and if you get started now, you can have plans in place so that construction can proceed quickly, whenever the weather allows. You'll be out there with seed packets in hand, long before the gardening season begins for everybody else.

SOURCES

-- Charley's Greenhouse & Garden; www.charleysgreenhouse.com

-- Gardener's Supply Co.; www.gardeners.com

-- Hartley Botanic; www.hartley-botanic.com

-- Growers Supply; www.growerssupply.com

(For editorial questions, please contact Clint Hooker at chooker@amuniversal.com or the Universal Uclick Editorial Department at -uueditorial@amuniversal.com)

Gardeners looking for colorful, low-maintenance plants are discovering that shrubs do the job and a bit more. Hydrangeas, azaleas and easy-care roses are claiming the spots where perennials once were preferred, and backyard landscapes are changing for the better.

The shrubs themselves are undergoing a transformation, too. "The trend we see right now is taking the classic shrubs like hydrangeas or lilacs and improving on them in some way," says Shannon Springer at Spring Meadow Nursery and Proven Winners in Michigan. Reblooming and long-blooming shrubs are one of the company's top priorities, she says.

Flowering shrubs have truly become the new perennials, says Tony Fulmer, chief horticulture officer of Chalet Nursery in Wilmette, Ill., near Chicago. Annual and perennial flowers remain popular, of course, but the big nursery's five teams of garden designers are making increasing use of hydrangeas, shrub roses, forsythia and other flowering shrubs -- especially compact forms -- in their landscaping plans for new gardeners just getting their fingers into the dirt and for everyone else in need of gardens and plants that don't require a lot of attention.

"Anything that performs well as a foliage plant and blooms for a long time, we are going to sell the heck out of it," Fulmer says. Chalet's retail and landscaping divisions sell millions of dollars' worth of plants every year; hydrangeas and shrub roses represent more than half of the sales of flowering shrubs, he says.

Shrubs have always been popular, but new introductions have exploded in the past few years, offering gardeners and designers more choices than ever before.

"What we have found is that designers are very solution-oriented," Springer says. Flowering shrubs with an extended season of bloom have a distinct edge "because people aren't just looking for two weeks of color." Gardeners and designers also want "shrubs that are more compact, less gangly, and look great in containers."

One of the most popular new hydrangeas is Limelight, a hardy, mid- to late-summer blooming shrub with large blooms that open with sparkling chartreuse petals, which change to creamy white and then fade to a soft, deep rose. Limelight and Weigela Wine and Roses, which has purple leaves and deep magenta flowers, "are our top dogs," Springer says. A new reblooming weigela called Sonic Bloom is part of the revolution of rebloomers, introducing an old-time favorite with modern characteristics to a new generation of gardeners.

Fulmer says garden-shop customers want "long-bloom, they want hardy, and they want no diseases, and plants that are insect-free. Now they also want compact habit." The Limelight hydrangea grows to six to eight feet tall, but Little Lime is only half that size. "It has been an amazing seller," he says. A new introduction, Bobo, which blooms so heavily that the leaves are hidden, is going to be even more popular, Fulmer predicts.

Shorter plants naturally need less pruning than shrubs that grow 10 feet tall or more. They fit more gracefully under windows, they will not block your view as you back down the driveway, and they are cozy companions in flower beds, where they remain in scale with perennial peonies, iris and daylilies. Compact shrubs never become thugs that turn a patio into a cave, and they add a graceful and manageable layer of color, texture and interest to the dappled light under trees.

Flowers have more appeal than foliage, Fulmer and Springer say, although bright chartreuse leaves, foliage with a coppery sheen or shrubs with variegated leaves all turn heads in a garden shop -- and in a garden -- especially if long-blooming flowers are also part of the package. Hybridizers are working to reinvent one-season shrubs, like deutzia and forsythia, introducing plants that bloom more vigorously in season, and look more distinguished when their flowers are spent.

Finding a spot for these new shrubs is easier than you think, Fulmer says. Removing an overgrown shrub makes room for new varieties and fresh design. Climate change and bugs and blights have also opened up some planting spots in mature gardens. Emerald ash borer, a destructive beetle that has spread to 18 states across the Northeast and Upper Midwest and is expected to kill millions of trees, has once again reminded city planners, garden designers and gardeners of the importance of diversity. As ash trees are replaced, understory plantings will also change.

"People who have had shade will have sun," Fulmer says. "They will mourn the loss of their trees, but people who are gardeners are going to be excited about the possibility of having sun and a different palette." Among the colorful ranks of flowering shrubs, there is a lot to be excited about.

SIDEBAR

TAKE YOUR PICK: GREAT FLOWERING SHRUBS

-- Hydrangeas are hot sellers, and there are many great choices. Let's Dance and Endless Summer cultivars are hardy mop-head hydrangeas that bloom all summer long with showy pink or blue flowers. Limelight and Little Lime bloom in mid- to late summer, with creamy white clusters of flowers that mature to deep rose. Bobo is a compact, especially heavy-blooming hydrangea. Quick Fire blooms early.

-- Compact and reblooming lilacs are growing in popularity. Miss Kim grows slowly to six feet tall and can be kept pruned even smaller. Bloomerang lilacs put on a show in spring and rebloom in summer and fall. (Clipping off spring blooms encourages rebloom.) They grow to about five feet tall.

-- Low-maintenance, long-blooming, colorful shrub roses "have made roses a lot more interesting to people," says Tony Fulmer of Chalet Nursery in Wilmette, Ill. Knock Out, Drift and Flower Carpet roses all bloom from spring through frost and can be pruned with hedge shears. They "have changed the rose business dramatically," he says.

-- Hybridizers working with flowering shrubs have made significant progress with rose of Sharon, which thrives in hot, sunny places. Azurri Satin and Sugar Tip are both seedless varieties, which means they will not become a nuisance in your garden.

-- Fulmer likes the Show Off series of forsythia, including the little Sugar Baby cultivar, which only grows to about 30 inches tall. In spring, the branches of these forsythia are covered with bright yellow flowers. They look like bright yellow bottle brushes, Fulmer says.

-- Shrubs with variegated or colored foliage sparkle even when they're not in bloom. Double Play spireas are adaptable and hardy, and their glowing foliage makes a nice backdrop for summer flowers. The cream-edged leaves of deutzia Creme Fraiche and the bright lime-colored foliage of deutzia Chardonnay Pearls stand out all summer, long after the spring flowers have faded.

CAPTIONS AND CREDIT

(NOTE: These photos are for ONE-TIME use ONLY. At Home photos, with the proper credits, are to be run ONLY with At Home stories. Conversion to black and white is OK.)

(For editorial questions, please contact Clint Hooker at chooker@amuniversal.com or the Universal Uclick Editorial Department at -uueditorial@amuniversal.com)

To bring your garden into focus, find a place where your eyes can rest.

Focal points are a garden's visual resting spots. In the flashy riot and exuberance of a summer garden, they lead the eye through it all, gently imposing order on a view. At every season, a tall, carefully placed urn, a sparkling birdbath or a handsome specimen shrub doesn't steal the glory from the rest of the garden -- it enhances the scene by giving it direction.

"The most common mistake people make is they try all these different varieties of plants, and their backyard ends up looking like a tossed salad," says Mike Miller, a landscape architect at Ewseychik, Rice & Miller in Longwood, Fla. "We use a broad, simple palette," he says, "and create focal points."

Finding a focal point and settling on an appropriate plant or architectural element to achieve the desired effect may take some thought and effort. Some designers actually give their clients a large, empty picture frame and ask them to walk around with it, defining the important views. If a picture frame makes you self-conscious, pick up a camera, instead: Taking pictures of your garden will reveal the places that naturally attract your eye; it might also reveal spots that need to be screened from view. You'll be able to forget about an annoying utility pole out there in your view if you plant a screen of evergreens and place an arbor strategically in your line of sight.

Peggy Krapf, a garden designer in Toano, Va., near Williamsburg, works hard on the details in her client's gardens. One suburban garden seemed to have all the right elements, but simply did not feel welcoming. "There were all these little bits," she says. "They had nice plants and paths and a fountain, but they were like separate thoughts." Visitors were not sure where the garden began or how to approach it, and the existing paths hurried them along without encouraging them to enjoy the experience of the plants along the way.

Krapf needed to unify the garden. She first suggested a proper garden gate. The 4-foot-high gate, flanked by evergreen shrubs, makes visitors pause a little before entering the garden, allowing them to take in the scene. Krapf then placed a bench at the end of the path, creating a destination, and moved a few shrubs to make the fountain the focus of the view from the porch. In another client's garden, she designed a curving stone bench to put in one corner: The bench draws visitors out to enjoy the flower beds up close and takes the sharp edge off the corner of the property.

In her own large country garden, Krapf put a garden bench at the end of an axis, about 50 feet from her front door. The bench occupies a space with raised flower beds on either side and invites her to sit there and admire her blooms. From the bench, looking back toward the house, she created a sort of focal point in reverse, framing the view of her own front porch between an oversized urn and a columnar boxwood.

"We often use containers as focal points around a door or on a patio," says Molly Moriarty, a garden designer and owner of Heart and Soil Design in Minneapolis. "We're shooting color where we need it," she says of these pots full of flowers, and at the same time giving structure to the whole setting. Containers can be a challenge through the winter in cold climates, but Moriarty uses combinations of twigs, evergreen branches, dried vines and seed heads in her winter pots: they bristle with texture and look especially pretty in the snow. When spring comes, she is ready to replant with cold-tolerant flowers such as pansies and with ornamental kale and cabbages.

Focal points -- like Moriarty's pots -- can have even more impact if they change through the seasons. Shifting light and shadows will affect the way you experience an arbor. You can enjoy the blooms and perfume of roses or other climbing plants in summer and the tracery of vines in the winter. A birdbath will attract different complements of visitors at various times of year. A specimen tree planted as a focal point will change through the seasons, too: A crabapple, redbud or another hardy flowering tree might be covered with blooms in spring and with berries or decorative seedpods in the fall and winter.

Even small gardens have room for more than one focal point, but it is best not to let them compete with each other -- if you can see three focal points at once, then the garden is already out-of-focus. And make sure the focal points you choose are in scale and in character with your garden. In general, sculpture, flowerpots or plants used as focal points should be large enough to command attention. Bold strokes are more effective than subtle touches. An armillary sphere or sundial on a plinth should sit well above the flowers around it, or stand all by itself. When your focal point stands out proudly, the rest of the garden seems to come to attention, too.

CAPTIONS AND CREDIT

(NOTE: These photos are for ONE-TIME use ONLY. At Home photos, with the proper credits, are to be run ONLY with At Home stories. Conversion to black and white is OK.)

(For editorial questions, please contact Clint Hooker at chooker@amuniversal.com or the Universal Uclick Editorial Department at -uueditorial@amuniversal.com)