NYT:

May 5, 2005
A Garden's Future, in Glass Houses
By ANNE RAVER
CONSIDERING that the earliest greenhouses, made by the Romans, were
holes in the ground covered with mica, the new $24.6 million Nolen
Greenhouses for Living Collections, which open May 14 at the New York
Botanical Garden in the Bronx, are a primrose's paradise.

"We'd never be able to grow these auricula primroses, because we
couldn't get them cool enough," Todd A. Forrest, the associate vice
president for horticulture and living collections said last week.

He stood by a table of astonishingly healthy, bright yellow, orange,
red and purple primroses, which are the stars of "Primrose Palette," an
exhibition of Victorian potted plants in the Bourke-Sullivan Display
House, one of the eight distinct growing zones in the Nolen
Greenhouses, which are under an acre of glass. It was 63 degrees, just
what primroses like.

Unlike the Enid A. Haupt Conservatory, the Victorian-style domed
confection built to display collections and plant shows, the Nolen
Greenhouses are devoted to growing plants - hundreds of thousands of
them, for display gardens and indoor exhibitions - and keeping rare
collections in prime condition.

The state-of-the-art greenhouses were designed by Mitchell/Giurgola
Architects of Manhattan, in collaboration with the Van Wingerden
Greenhouse Company, in Horseshoe, N.C. And just about everything, from
the roof vents that open on a sunny day and close when it rains, to
evaporative cooling systems that click on when one of the rooms gets
too hot, is controlled by computer.

"It allows us to grow a greater number and diversity of plants for all
of our projects and programs," Mr. Forrest said.

Under these controlled conditions, scientists can now grow plants for
research studying the DNA of a primitive nonflowering plant like
selaginella, for example. Gardeners can now plant the seeds of Victoria
amazonica, the largest water lily in the world, in a pool kept at 80
degrees.

Behind-the-scenes tours of the greenhouses will be held next Saturday
and Sunday, so that visitors may see the plants and learn how all these
bells and whistles work.

Those perfect primroses, as well as ferns and fuchsias, will be on
exhibit through June 12, at the Bourke-Sullivan Display House, which
will remain open throughout the year, allowing visitors to see
gardeners at work.

The new structure doesn't just make the plants happy. It's a paradise
for the 50 gardeners here, as well.

The old propagation house, or prop, as it is affectionately called, was
built in the 1950's, and was strictly off-limits to the public.

"It was a warren of glass houses, pits and frames held together with
chewing gum and baling twine," said Mr. Forrest.

In winter, gardeners had to crank down all the vents and bring in the
salamander heaters. In summer, they opened all the vents and brought in
fans.

But here, in the Nolen Greenhouses, vents are constantly adjusted
according to the needs of plants in the eight different growing zones.
In some of the cool houses, roof vents 22 feet overhead were wide open
to the sky last week. In the display house, however, the roof vents had
closed, and the side vents had opened, to allow an evaporative cooling
system to cool and moisten the air, without letting it escape through
the roof.

Big exhaust fans were whirring as they pulled fresh air through a panel
high on the wall, where water dripped down spirals of waxed cardboard.
This cool, moist air was about as close to a stream bank in spring as
these primroses will ever get.

Hydro fans can also mist plants, when sensors register low humidity.

The new greenhouses feature other automated systems to respond to the
weather. If the sun gets too bright in the fern house, for example, a
shade is automatically pulled overhead, to protect fronds from burning
and to help cool the air. If clouds roll in, the shade rolls back,
letting in more light.

The old prop had no such flexibility. Every spring, gardeners would put
up a shade cloth, and it stayed on all summer.

"Cloudy, or shady, it didn't matter," said Marc Hachadourian, a
gardener who tends the 7,000-specimen orchid collection. "In this
facility, we never have plants in the dark all the time." Gardeners no
longer have to move plants to catch the right light. The plants remain
in place, and the computer-controlled system adjusts the light for
them.

Hot water pipes coursing beneath the floors produce radiant heat, which
can be controlled from room to room, depending upon how much bottom
heat particular plants need. Most seeds, for instance, germinate best
at about 70 degrees. And tropical plants need warmth around their
roots.

It only took a few weeks for tropical plants, after being moved to
their new home, to put out vigorous new growth. A Manilkara zapota, a
tree that produces a milky sap called chicle, once used in chewing gum,
grew two feet. An iboga, a medicinal plant from West Africa that had
lost its leaves last winter in the cold prop, was bushy and green.

In the plant production zone, perfect conditions were producing tens of
thousands of perfect perennials and annuals. Hundreds of foxgloves were
blooming on five-foot stems, all at the same height, with what appeared
to be the same number of velvety spotted flowers. These would soon be
whisked over to the Conservatory, to freshen up the vanguard of
bloomers at the Spring Flower Show, which runs through June 12.

And next spring, in the 80-degree pool at the orchid house, those
Amazonian lily pads are expected to grow to two or three feet wide
before they will be trundled to the courtyard pool at the conservatory,
where their flowers will bloom by late summer, over pads that can grow
to be six feet wide.

At the Nolen Greenhouses, almost anything is possible. Even the largest
orchid in the world, Grammatophyllum speciosum, from New Guinea - about
the size of a Mini Cooper, with flower spikes 10 feet tall - has plenty
of room.



--j_a

CONSIDERING that the earliest greenhouses, made by the Romans, were
holes in the ground covered with mica,

Does anybody have any references to this style of greenhouse that I may be
able to look up???

Kye.