TOUCH OF SPRING: GREENHOUSES DON'T SWEAT THE WINTER WEATHER

These flowers of a cyclamen plant at the university greenhouse should be in full bloom in about five days.

Several hanging baskets of torch begonias are kept at the university greenhouse.

Pink carnation flowers are growing at the university greenhouse.

While the rest of us wrestle with the arctic temperatures, greenhouses remain unaffected by Old Man Winter.

Thanks to greenhouses, people still can get poinsettias at Christmas, which normally survive only in tropical or subtropical regions. At Easter, they can line their window sills with lilies, which require shelter from strong winds.

They can also get a head start on their spring planting by getting them from a greenhouse while the plant life outside hasn't even begun to open its eyes.

"The cold doesn't affect the inside at all," said Denise Pingle, manager of the greenhouse at Southeast Missouri State University. "We're warm inside all year round and we're growing plants despite the cold outside."

The temperature is kept at about 70 degrees all year, she said.

"The cold is not much of a problem," said Paul Schnare, owner of Accu-Grow Sunnyhill Gardening Center and several greenhouses in rural Cape Girardeau County.

What people don't know is that there are certain things that have to be done to make sure that greenhouses are functional.

"What you've got to make sure of is that there are no holes that allow cold air and wind inside the greenhouse that could harm the plants," Schnare said.

He said heaters have to be checked all the time to make sure temperatures are constantly as warm as the plants and flowers require.

Some greenhouses have generators in case the heaters quit due to an electricity malfunction.

Greenhouses are buildings of plastic or glass, which allows for the entrance of sunlight. A greenhouse's controlled environment allows for the growth of plants and flowers year-round.

A greenhouse's roof is slanted to admit a maximum of sunlight when the temperatures drop. A greenhouse is a solar collector, trapping the sun's heat.

But in the winter, greenhouse owners fire up heaters and furnaces to keep the temperature right where it needs to be. It sends steam, hot water or hot air through pipes to warm the building.

A few greenhouses have special solar collector devices that absorb the sun's heat energy and transfer it to water in a storage tank beneath the greenhouse floor. The stored hot water heats the greenhouse on cold nights.

While greenhouses are impervious to cold, snow is a different story entirely. If snow or ice accumulates on the roof of a greenhouse and isn't properly disposed of, it can cave the glass roof of the greenhouse.

Pingle and Schnare know that better than most. The roof of the university greenhouse collapsed from the weight of snow in 1979, Pingle said.

Schnare said that his greenhouse roof collapsed several years ago, too.

Now when it snows, Pingle said, the university wastes no time in getting on the roof and sweeping the snow off.

But flowers aren't the only thing being grown in greenhouses. Vegetables such as cucumbers, lettuce and tomatoes are grown in such structures and sold out of their growing season to consumers.

Many commercial growers operate greenhouse ranges, which consist of two or more greenhouses.

And there are advantages to working in a greenhouse, too, Pingle said. "It's better than being outside."