Cold injury above freezing | Germinating Virginia creeper seeds
New Mexico State University

# Issue: October 14, 2000

• Cold injury above f1eezing
• Germinating Virginia creeper seeds

## Cold injury above freezing

Question:

Will a temperature of 33 degrees Fahrenheit hurt any type of common houseplant or outside plants?

The answer is yes! Many plants can withstand temperatures below freezing, many can tolerate temperatures near freezing, but some cannot tolerate low temperatures even when the temperature is above freezing. The time the plant must endure the cold temperature is also a consideration. Longer durations at a low temperature will result in more injury.

Many houseplants are from the tropics and very sensitive to low temperatures. As a student, I grew a plant called flame violet (Episcia) that died each year just after the Christmas vacation. When I went to my parents' home during the Christmas holidays, I set the thermostat at 50 degrees in my apartment. Later, after several dead plants, I realized that the low temperature killed my flame violet. By keeping the temperature near 60 degrees, subsequent flame violet plants survived without injury. I believe this is one of the most sensitive plants to "chilling injury", but there are many others, including common garden annual vegetables and flowers, which will also exhibit injury at low temperatures above freezing.

I must also ask how you are measuring the temperature. Temperatures measured in one location may vary by several degrees from temperatures in a nearby location. Low temperatures reported by the news or weather service may vary considerably from the temperatures in your garden. If you measured a temperature of 33 degrees or heard it reported on the news, it is very likely that temperatures below freezing existed somewhere in your landscape. If your question is based on the observation of frost damage when your thermometer said it didn't freeze, this is probably the explanation.

## Germinating Virginia creeper seeds

Question:

How does a person germinate seed for a Virginia creeper vine?