Purdue Extension Service

It's Deja Vu All Over Again: Weather Fluctuations Threaten Landscapes

By Larry Caplan, Extension Horticulture Educator, Vanderburgh County, IN

For the Evansville Courier and Press, February 8, 2008

Former baseball manager Yogi Berra once uttered the surreal comment "It's like deja vu all over again." I'm reminded of that interesting turn of phrase as I watch the weather reports.

This year, just as last year, we've undergone fairly quick extremes in temperature fluctuations. Within the last couple of weeks, we've gone from temperatures in the 50s to below freezing in a matter of hours while experiencing tornadoes and thunderstorms (all of this in January). A sudden icy blast of snow came through, to be followed by more temperatures in the 50s.

This confusing flip-flop in the weather is certainly not going to do good things for our landscape plants. Many gardeners have reported bulbs emerging from the ground for nearly a month. Many trees have swollen buds, and a few flowering cherries had already started to bloom before the last freeze. Most of this exposed plant tissue is likely to have been frozen off by the cold weather. The question, though, is will we continue to see more plant injury as the season goes on?

There's no way to predict what our gardens will see in the next couple of months. In fact, I heard a report last week that Punxsutawney Phil, the famous weather-predicting groundhog, was seen flipping a coin before coming out of his den on Groundhogs Day.

This I do know: IF we continue to experience early spring-like weather in February, then our plants will continue to develop, sprout, and bloom. The more warm days above 50 degrees, the further along our plants will be. IF we then get another cold snap (which is almost a certainty at this point), then we can expect to see cold damage at least as severe as what we experience last year in April.

There's not a lot we can do at this point. I would suggest planting bulbs and perennials a few inches deeper next fall, to give us a little more insulation by the soil. Mulching the flower beds after the ground freezes the first time may help trap the cold and slow down the development of our plants. I would definitely avoid planting flowers and vegetables early this year; even if we do get a warm spell that gets you itching to do some gardening, delay planting until the danger of freeze is over.

There's nothing practical we can do to protect our flowering and fruiting trees. If they bud out early, a late freeze will destroy the crop...period. If we avoid the freeze this year, we may expect an overabundance of fruit as the trees try to compensate for last year's freeze injury. Fruit thinning, performed about 30 days after petal fall, will be necessary for best fruit quality.

For more information on fruit thinning and protecting your garden from cold injury, contact the Purdue Extension office at (812) 435-5287.