Flower Catalogs Boast
An Array of New Hybrids

Across the country mailboxes are overflowing with spring gardening catalogs. These glossy wish books crow about this year's new plants, from a two-toned, bronze-colored rose "that makes your eyeballs salute" to a gold-leafed ornamental grass that is "surely the envy of King Midas!"

But before you dial that 800-number to order consider this: Some new plants are downright gimmicks -- the plant-world equivalent of clear Coke -- designed more to boost growers' profits than to beautify your garden. Who, for example, really needs lime-green peony flowers?

Yet beyond the aesthetic questions is a more important issue. These new plants may not be as hardy as advertised. Either they may not thrive in your garden, or may never return the following spring as promised. Much as car experts warn consumers to shy away from a vehicle in its first model year until it establishes a track record, plant lovers should use similar caution.

Several years ago, the plant industry sold countless gardeners a disappointment called the coreopsis Limerock Ruby. Coreposis, a daisy-like flower commonly called tickseed, is a tough, dependable perennial that typically blooms in shades of yellow. But Limerock Ruby has flowers of bright cardinal red -- an unusual color for any perennial and one never before seen in a coreopsis.

So pleased was the gardening industry with the new flower that the Mailorder Gardening Association gave it a "Green Thumb Award" in 2003. The group stated that Limerock Ruby "thrives in sunny locations throughout zones 4 to 9," referring to the U.S. Department of Agriculture's hardiness zones. (Zone 4 includes parts of Northern states such as Vermont and Minnesota.)

Seductive Descriptions

Like many gardeners seduced by the glowing descriptions I bought several Limerock Rubys. But the plants didn't survive their first winter in my zone 5 garden.

My experience isn't unique. While gardeners in mild climates still praise the plant, those in colder regions were frustrated. Many gardening-oriented Web sites are full of tales of untimely Limerock Ruby deaths.

These days the plant industry has severely downgraded its winter-worthy claims for Limerock Ruby. The company that originated the variety, Blooms of Bressingham, now calls it a "tender perennial," which means the coreopsis isn't likely to survive winter in the Northern half of the country. Some catalog concerns, including industry giants White Flower Farm and Wayside Gardens, no longer even carry Limerock Ruby.

How do such mistakes happen? The nearly $70 billion U.S. lawn-and-garden industry needs eye-catching new stuff to sell each year, just like the fashion industry needs new clothing styles to lure consumers. After all, gardeners can quickly become jaded by the usual assortment of age-old dahlias and daffodils. So the big growers pounce on any novel variation in plant shape or color that shows up in their fields naturally or that is created by plant hybridizers. Typically, they hype the new plants on catalog covers and Web site home pages, and charge more than for older varieties.

A Flop in Zone 5

Limerock Ruby was a natural variation discovered by Mary Ann Faria, the owner of a retail nursery in Lincoln, R.I., called Limerock Plant Farm. She took the red-blooming coreopsis to Blooms of Bressingham, a reputable British plant-industry marketer whose North American affiliate is based in Sacramento, Calif. Blooms of Bressingham put the coreposis through its usual multiyear testing for new flowers, in which samples were sent to several plant propagators in different parts of the country, says Christine Kelleher, a Blooms of Bressingham spokeswoman.

All the tests showed Limerock Ruby to be a hardy perennial that would survive winter in much of the country. But it didn't. "We still don't know what happened," Ms. Kelleher says. One thing the company has discovered is that the plant can't stand overly wet soil, but that probably doesn't explain the number of problems Northern gardeners experienced.

Since then, Blooms of Bressingham has changed its procedures. It now tests new plants with far more experts and gives them more time to study them. It also has cut back on how many plant varieties it introduces each year, to further boost quality. "That experience has caused us to be more cautious," Ms. Kelleher says.

Testing Can Be Tricky

New plant varieties such as Limerock Ruby may be more or less hardy than their parent plants depending on which genes they inherit, says Marvin Pritts, chairman of the Horticultural Sciences Department at Cornell University in Ithaca, N.Y. "Cold hardiness ... is a complicated physiological process, and many genes scattered over multiple chromosomes are likely involved in its control," he says.

Testing a new perennial for winter durability can be tricky. A plant may be able to tolerate freezing weather in January, but a cold snap in spring after it starts regrowing could kill it, Prof. Pritts says. And should fall weather turn cold suddenly, rather than gradually, that also could do in an otherwise hardy plant. So unless a plant in the testing phase endures all these conditions, its real ruggedness may not be known.

Of course, most of the dozens of new varieties of flowers, shrubs, vegetables and trees introduced each year grow as promised if they are given proper care. Some are even true breakthroughs. One such innovation is the popular Endless Summer hydrangeas, which were tested in Minnesota for winter toughness before they were rolled out to gardeners last spring. These "mophead" hydrangeas -- previously difficult to grow in Northern states -- develop masses of big blue or pink flowers no matter how harsh the previous winter. That's because they can bloom on new stems, instead of needing to bloom on "old wood" that grew the prior year, as with most other varieties. The Endless Summer shrub can die back to the ground during a hard winter but still produce abundant flowers the next year.

Or at least that's what the big grower behind Endless Summer, Bailey Nurseries Inc. of St. Paul, Minn., says. Gardeners who snapped up these shrubs last year (including me) won't know for sure until spring.

So go ahead and ogle the plant catalogs. But be a bit cautious. New gardeners "should stick with the tried and true," says Stephanie Cohen, director of the landscape arboretum at Temple University in Ambler, Pa. More adventurous gardeners probably should limit themselves to just one or two of a new variety and give them a year's tryout, she adds. For added safety, buy a plant that's rated as being hardy in a zone colder than yours.

In any case, most reputable catalogs and many garden centers will replace a plant that doesn't survive. "Gardening is a learning experience," Ms. Cohen says.

-- Kara Swisher is on vacation.

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