Krause, now a retired family doctor living in Whitemarsh, has long since identified those memorable blooms: Hydrangea arborescens 'Annabelle,' also known as snowball hydrangea. And she credits them with sparking a lifelong fascination with this American garden favorite.
"I still buy 'Annabelles,' " she says.
Besides their sentimental pull, hydrangeas - including many new varieties - have other qualities to recommend them to gardeners. And Krause, a master gardener, often does.
"They're a real no-care plant, and they look good all year," she says.
Hydrangeas grow in a range of climates - from warm to cool to seashore - as shrubs, small trees or climbers. At their best in summer and fall, some tolerate sun, others shade, and most the vast territory in between.
They have diverse personalities, too, from massive to dainty, flamboyant to demure.
Massive and flamboyant would be Hydrangea macrophylla, the bigleaf Japanese native whose familiar "mopheads" of pink, blue or purple are considered the quintessential hydrangea. No question, they deserve the accolade.
But the bigleaf "lacecaps" are lovely, too, and more subtle. Their romantic, slow-waking florets form a bouquet of stars.
H. quercifolia or oakleaf hydrangea, another U.S. native, is named for the shape of its large leaves. These white flower pyramids turn rose and taupe in the fall, while the leaves bleed burgundy, bronze and purple.
For those who know it, this hydrangea surely ranks among the most splendid of all.
Best known in the H. paniculata category is PeeGee, a nickname derived from the botanical name, H. paniculata 'Grandiflora.' (Sometimes, garden centers confuse the issue by calling all paniculatas PeeGees, but now you know.)
Paniculatas look a lot like oakleafs, but their cone-shaped flowers are longer, and their leaves are oval.
Then comes Hydrangea anomala petiolaris, a climbing hydrangea that many gardeners have yet to discover. It has broad, heart-shaped leaves and lacy white flowers that, over a few years, will quietly cover a wall or arbor with an exquisitely textured green blanket.
Not exactly what comes to mind when you think "hydrangea," but that's the point. This plant family's variety and beauty appeal to gardening experts and novices alike.
"We have a ton of hydrangeas here. We use them in a lot of different ways," says Andrew Bunting, curator of Swarthmore College's Scott Arboretum, where they're both grouped en masse and scattered about the grounds.
Bunting uses hydrangeas in his own garden, too. He's planted oakleaf as a backdrop for perennials and shrubs and Japanese H. serrata, which is like a compact bigleaf, as accents or foundation plants "tucked here and there."
By now, you're getting the picture: Hydrangea enthusiasts have a hard time choosing just one.
"I wouldn't know where to start," says Judith King, who's been hooked on hydrangeas for 20 years and started the Web site www.hydrangeashydrangeas.com a decade ago.
"I love oakleafs, PeeGees - I love them, too - and paniculatas, they're all just special," says King, who grew 50 hydrangeas in her South Carolina garden before moving to a townhouse in Falls Church, Va.
The Victorians also loved the hydrangea's formidable size and pizzazz, and beginning in the 1930s and '40s, the plant became a fixture in many American gardens as well.
But over the last 20 years, its popularity has taken off. Now, pots of single hydrangea hyperblooms are a mainstay of the holiday flower trade (especially Mother's Day), and garden centers are loaded with mopheads and other kinds.
Bunting, of Scott Arboretum, thinks this is the result of several trends.
It's become easier for big wholesalers to import plants. Breeding, hybridizing, trademarking and marketing new plants has become big business. And, he says, at least in the case of the oakleafs and snowballs, consumers are clamoring for more native plants.
But one has to think that, at some point, the industry realized the same thing we did: that hydrangeas are beautiful, easy to grow, fast-growing, long-lived, and tough.
Who doesn't want a plant like that? Better yet, who couldn't grow one?
These days, even living in an apartment is no impediment.
"Hydrangeas used to be too big for most home gardens, but not anymore," says Krause, who loosely bubble-wrapped a Japanese dwarf variety in a pot on her apartment balcony over the winter.
"That's not a recommended horticultural technique," she says, "but it worked."
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Contact gardening writer Virginia A. Smith at 215-854-5720 or email@example.com.