By Adrian Higgins
Thursday, March 25, 2010; GZ12
Blue is a special color in the garden. People want to turn their pink-flowering hydrangeas blue, not their blue ones pink. So when blue shows up in a flower that is supposed to be another color, the gardener is wired to go wild.
Such is the case with a very special poppy: not the blood-red poppy of our late-spring gardens, but the blue poppy of the Himalayas.
First seen by Westerners in the 19th century, the blue poppy was collected and championed by an intrepid British explorer in the early 20th century. To see the nodding, elongated flower buds open a glowing baby blue must have made all the hardships and travails of Frank Kingdon-Ward seem worth it. "The flowers flutter out from amongst the sea-green leaves like blue and gold butterflies," he enthused in his diary. The gold is a reference to the anthers, themselves ornamental.
If this is so great a plant, you ask, why haven't you seen it? There are mail-order nurseries that peddle this poppy, but dubiously and to the unknowing, because the only regions of the United States where this miraculous flower has a chance in the garden is in parts of New England, the Pacific Northwest and Alaska.
It is a plant of the cold but sunny Himalayas, growing above 10,000 feet. Beyond its need for a certain rarified terrain and climate, it has a stubborn streak that makes it not just hard to grow in the mid-Atlantic, but impossible. This, of course, adds to the allure.
There is an exception to every rule. If you hurry, you will see the last of this season's blue poppy display in the Main Conservatory at Longwood Gardens in Kennett Square, Pa. This is one of very few places in the United States to see them.
Gathered in wall planters at the edge of the adjoining water-mirrored Exhibition Hall, the poppies are refreshed from a cache of 190 that come into fleeting bloom over a three-week period each March. The plants rise to about four feet. The soft leaves and stems are covered in golden hairs, topped with just three or four pendant blossoms.
Visitors may not know the magnitude of this feat, but they do realize that seeing a blue poppy is magical, a bit like being transported into the color-skewed Land of Oz, itself entranced by the poppy.
Suitably beguiled, visitors line up to take photos of the blue poppy. "It's not a big display, but there's something about it," said Jim Harbarge, a leader in Longwood's research and production division. "Maybe it's that holy grail."
Because the poppies are elevated in their containers, you can look closely into the face of these oddities. About three inches or more across, a bloom consists of four slightly cupped petals that gather around a central hub of stamens and pistils. The blue is light but intense. The pollen-laden anthers are like a golden asteroid belt suspended around the pistil, itself sheathed in spiraling white hairs.
I can imagine some growers I have encountered keeping the secrets of such cultivation to themselves, to add to the mystery and value of the plant, but Harbarge is happy to talk about the methods used to trick this grudging prima donna onto Longwood's stage.
Harbarge and his colleagues became interested in raising the blue poppy, botanically the meconopsis, when a graduate student, Shannon Still, approached him about writing a thesis on the plant. They found a device that measures photosynthesis, the leaf's process of turning sunlight into energy and food. As temperatures climbed into the 60s, it became clear that the plant couldn't photosynthesize enough to keep up with its respiration. Still "could really see at what temperature the plant began to suffer," said Harbarge. "At 70 degrees, roughly, they would burn themselves out."
In mid-October, Longwood's blue poppy grower, Juergen Steininger, receives year-old plants by air freight from a nursery in Alaska. By that time, the plants are going into winter dormancy, when the leaves would naturally shrivel and the roots and crown hunker down for the season.
The poppies are potted in a free-draining mix, placed in a darkened cooler and kept at 34 degrees until early January. This fools them into thinking they have gone through a winter. They are then potted up and brought into a cool greenhouse, where temperatures of 45 to 55 degrees coax fresh growth and, by early March, flower stalks.
The species championed by Kingdon-Ward was Meconopsis betonicifolia. Longwood displays a strain called Lingholm, a hybrid of two species that is known as M. x sheldonii. Given the plant's quirkiness, it can neither be propagated nor made to reflower the following year, even in the controlled environment of the greenhouse.
This year's crop has more purple streaking on it than anyone wants, but that's a function of February's snows. As the storms began to produce record snowfall, Steininger had to crank up the temperature in the greenhouses for almost a week to prevent snow loads from accumulating on the roof.
"Extended temperatures over 65 degrees will slowly kill this plant," said Steininger. In other words, don't try this at home.