The first five days of 2018 saw low temperatures in the teens in Elizabeth City. Night temperatures hovered in the single digits the next three nights, one of them around zero. During that stretch daytime temperatures remained in the 20s. Mercury reached into the 70s four days later.
Weather fluctuated for a while until about the tenth of February when things turned warm again. We had no frosts until March 5th and daytime temperatures frequently topped 70 degrees. It’s natural to ask if this means anything and if so what are the implications?
Judging from all the flowers one might think it was late March or early April. Pears, saucer magnolias and forsythia have been in full bloom since mid-February. Mild nights are likely more responsible than anything. However, when daytime temperatures consistently flirt with the 80s and root zones warm, dormancy ends.
In most years plants break dormancy gradually. Take sugar maple for example. I used to make maple syrup and collected sap well before any visible signs of bud swell. Were there any sugar maples around here, this spring would have been lousy for syrup yields.
Sap runs heavy when daytime temperatures are cool to mild and nights are below freezing. If night temperatures consistently run above freezing leaves and flowers develop and sap flow stops. Once plants break dormancy they’re far more susceptible to winter injury.
This is the part that concerns me. It’s early March and we could yet have some very cold temperatures. The further plants progress into active growth, even a light frost could injure them. Should temperatures suddenly dip into the mid-twenties all foliage could be killed and plants would have to form new buds and start again. If fruit buds die trees would be barren this year.
Because of the mild February many folks have the itch to plant gardens and flowerbeds. My advice is, unless one is prepared for poor stands and stunted plants, waiting a few weeks is the best option. Raised beds, plastic mulches, row covers, cloches and even space heaters can provide extra insurance toward success. It’s still a gamble.
Mild air temperatures have pushed trees and shrubs. However, soils are still wet. Working soils when they’re wet destroys soil structure. This results in poor water movement, cloddy soils, standing water and stunted roots.
It might sound like I’m being negative about this mild weather. I’m not. We had some harsh weather in late December and early January and evidence of winter injury is everywhere. All foliage is dead on my big eucalyptus, and I’m not sure if the inner bark is damaged on the main trunk. I’ll have to wait and see if buds develop. My loquat got hammered too.
This unseasonable weather hastens determining winter injury to landscape plants. Bud swell means plants aren’t dead. If no buds have begun to grow people can check for live bark trees and shrubs by scraping small sections and hoping to see green. Cut back to the green and hope. As far as planting goes, be patient.
Here comes the update. As for the temperatures since March 5th, things have been different. We’ve avoided severe cold temperatures but have had several freezes, none severe, and daytime temperatures have been cool. This has ruined some of the beautiful flowers but it has also slowed growth and that has been a good thing. Everything is so wet that gardeners have been slowed too.
Ted Manzer teaches agriculture at Northeastern High School (firstname.lastname@example.org).