It might be winter, wet and cold outside, but inside the greenhouse at Humboldt State University it is warm and tropical, especially after the recent completion of a $300,000 remodeling project. A new heating and ventilation system in the geodesic

dome section, along with ventilation improvements and computerized controls for the entire facility, brings the greenhouse up to date in the 21st century. The $2.5 million greenhouse, covering roughly 12,000 square feet, is the largest in the CSU system and a valuable asset for North Coast residents, according to greenhouse manager Bill Weigle.

 Bill Weigle among the cycad collection.

"We are the only facility of this kind within 300 miles, so we really try to be not only a teaching facility for the college, but also an integral part of the community, especially for people who like gardening and who like to study plants," he said.

The greenhouse, open to the public free of charge five days a week from 8:30 a.m. to 4:30 p.m., is divided into nine different climate-controlled rooms, from desert to aquatic, temperate to tropical. Weigle estimates that there are 3,000 plants representing 180 families in the facility.

"We have almost every genus of conifer and we have one of the best fern collections," said Weigle.

The 2,000-square-foot geodesic dome section required the most renovation because when the new wildlife and fisheries building located on the east side was constructed, it blocked the greenhouse's morning sunlight. In addition, afternoon sun reflected off the brick building, causing the greenhouse to heat up excessively. The old ventilation system could not cool the dome adequately so a new system was added.

"What we've done is cut out the concrete (from the concrete perimeter foundation) and put in new registers so we can push in air from outside. We can also open up the top and we have a special fan that will evacuate the hot air out," Weigle explained.

In addition, a system of small quiet fans have been added to circulate air, along with a perimeter heating system of copper pipes and radiator tubes with aluminum fins. It is the most efficient way to heat the house. "This system is the best the greenhouse industry has to offer. You don't get anything of any higher quality," Weigle said.

A computerized fogging system that can cool the dome's environment as much as 10 degrees in less than a minute is another modern innovation. These changes allow the greenhouse manager greater control over the environment which ultimately will benefit the university's extensive plant collections.

"To me it is a real exciting thing to do, to achieve that balance that not only makes plants grow better, but controls fungus by using climatic control and also helps control pests and predators by providing temperatures and conditions that they need," Weigle said. "Now, instead of coasting and taking what we can get, we have the type of climatic controls that will allow us to be in charge and make any kind of environment we want," he added.

The diversity and quality of the plants in HSU greenhouse have a reputation with universities all over the country, according to Weigle. "Whenever I contact other universities and tell them I am from HSU on e-mail and that I am interested in trading for other plants, they get right back to me because we have things that people desire," said Weigle.

Trading plants with other universities is an economical, effective way to increase the collection, especially with an annual budget of $1,500 to spend on seeds, plant material, soil and pots.

"I've traded with different universities some of the ferns that we specialize in for an orchid collection from Dartmouth because we didn't have an orchid collection. Dartmouth said our fern collection was material to drool over," Weigle said.

 Bromiliad

A tour of the greenhouse will reveal a wide variety of plants like hibiscus, cycads, bromeliads, plumeria, exotic salvias, carnivorous plants, in addition to a collection of cacti and succulents. Tropical edibles that we take for granted include cashew, cinnamon, chocolate, sugar cane, ginger, banana and coffee.

"It is surprising to me how most people don't even know what their food looks like (in plant form). They have never seen how this stuff grows, and I think it just real enlightening for people to say `So that's where bananas come from. That's what ginger looks like,' " he said.

Rare plant specimens can be found in the collection as well. The rarest are the 30 Cathaya pine seedlings, Cathaya argyrophylla, sprouted from seed imported from China.

"I only know for sure that the Missouri Botanical Gardens and either North Carolina State or University of North Carolina have them. We are going to be experimenting as to how the pines handle our climate. Are they greenhouse only or will we be able to grow them outside?"

A unique ecological balance has been achieved in the greenhouse so that chemical pesticides have not been used for the past 17 years.

"We use beneficial insects, biological controls," explained Weigle. "The beneficial insects consume harmful pests and over the years the greenhouse has achieved a balance," Weigle said. "We have to allow a certain amount of pests, or else all of our beneficials will starve to death and die. We feel we can live with some pest damage and maybe that pest damage is beneficial because people can learn to recognize what thrip damage is and what mite damage is," he explained.

Educating students and the public is the primary goal of the greenhouse. "It is really sketchy to study botany from a book, but if you can actually come in and see the plants and observe them over a period of time, you get a much more complete picture and an appreciation of what is going on," he said.

With the exception of the dome, all plants housed in the facility are in containers placed on aluminum greenhouse benches. The floor is concrete and clean. One hears the monotonous din of fans heating and ventilating the environment. But the highlight is the dome, where tall tropical trees, lush ground covers and exotic flowering plants sprout from the soil. Construction work has created a bit of chaos, but Weigle is revamping and improving the landscape. When the project is completed, you will not hear the low roar of fans here and instead listen to the sound of rain pecking the roof.

"I want to make this a subtropical environment where you come in here and you have escaped from your daily life," Weigle said. "You are in the tropics and surrounded by the plants that are indigenous to those areas."

Terry's Garden Checklist for January

• PROTECT Frost-tender plants like citrus, brugmansia, passion flower, pelargonium and the like should be covered when the nights are cold and clear. Move container plants next to house under the eaves. Cover established plants with burlap or cardboard boxes. Well-watered plants withstand cold temperatures better than thirsty ones.
  
• SHOP January is bare-root season, a time to buy your fruit trees, roses, berries. Strawberries, blueberries, cane berries as well as artichokes, asparagus and rhubarb are available bare root. Look for bare root ornamental vines, shade trees, shrubs and perennials also.
  
• ADD COLOR Perk up empty flower beds and containers with colorful primroses, Iceland poppies, English daisies, calendula and candytuft. Pansies and violas turn winter into spring here on the coast.
  
• BROWSE Relax on a rainy Saturday afternoon and browse through the seed catalogs. You will find many new and exciting varieties of vegetables, annuals and perennials. Order seeds early to get the best selection. Now is a good time to plan for spring.
  
• PRUNE Annual pruning of dormant deciduous plants like cane berries, flowering vines, fruit and shade trees and roses should be started this month. Do not prune ornamental flowering deciduous trees and shrubs until after they bloom.
  
• BEWARE Fall planted bulbs are sprouting by now, so be sure to protect them from hungry slugs and snails. Bait or trap.