Warming the Wisteria

By Alice Le Duc

director of education

Each year as the March weather starts to show signs of spring, the staff at Sarah P. Duke Gardens watches the wisteria on the pergola with a careful eye on the night temperatures.

As the flower buds swell and start to expand with those warm days, the night temperatures become critical. Everyone anticipates the beauty of the wisteria-covered pergola in early April.

When I joined the Gardens staff in 2000, everyone told me how beautiful the pergola and wisteria were in spring. Little did I know that it would be April 2003 before I would see the display! Late March frosts damaged the buds my first two years here.

In 2004, the wisteria was again in danger of freezing. So the horticultural staff decided to fool Mother Nature. They set heaters in the pergola, providing enough warmth to prevent damage to the young buds. What a spectacular year that was.

Now the staff monitors the weather each year. With luck and the help of heaters, we try to present the beauty of spring with a lush wisteria-covered pergola.