Autumn Inside the Greenhouse

I felt the firm grip of fall as I walked the half-mile from the parking lot to the Conservatory Greenhouse at the University of Minnesota, where I volunteer. The temperature outside was in the 30s, and the wind whipped at my face. Yesterday there had been snow flurries.

In stark contrast to the outside world, the greenhouse climate was quite different. Part of the greenhouse is maintained at near-tropical temperatures. But other sections of the greenhouse are kept significantly cooler to support plants that have evolved in seasonal climates. Although indoors, autumn has arrived here too. The sunlight dims, and the nights grow long. Inside these cool greenhouse rooms the plants shed their leaves and virtually cease growth for the winter months, just as they would outdoors.

Part of my assignment for today included the pruning of yellowing and brown leaves. Removing the dead foliage from the plants and the floors helps to reduce the overall risk of mold and other pests affecting the dormant plants.

Resembling maple leaves, the American sweetgum (Liquidamber styraciflua) is native to eastern North America

Another task for today was to attach labels to the pots of oak saplings - 16 different species of them - indicating which days the pots were to be watered. I also attached identification tags to the exterior of the pots for easier reading.

California live oak (Quercus agrifolia), an evergreen oak native to California and Baja, Mexico

Not all plants in the temperate rooms are experiencing death and dormancy. Many orchid species bloom during the fall and winter months. As I swept fallen leaves I notice a couple of orchid beauties:

Reminiscent of ruffled skirts and high-stepping ladies dancing the cancan this orchid is a hybrid of the wilsonara species

Tracy's cymbidium orchid (Cymbidium tracyanum) has delicate hairs decorating the lip (labellum). The hairs assist by dispersing the scent meant to attract pollinators, and they dissuade predator insects from feeding on the petals (Wikipedia).

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