In the article *Winterizing Plants: Cold Damage, Julie Weisenhorn, U of MN Extension horticulture educator says, “Lack of snow cover and dry, droughty conditions negatively influence winter soil temperatures and cause root injury.”  

In Minnesota, the earth rotates on its axis at about 700 mph. The ground beneath our feet, known as the earth’s lithosphere, is in constant motion also. Yet we don’t “feel the earth move under our feet”, unless an earthquake occurs or you’re Carole King. Instead, we see the effects of this movement. We see it in the passage of a 24-hour day, in the cracks of an asphalt driveway, or the heaving of landscape edging over an extended period of time.  

We also see the effects it has on our perennials as this heaving occurs. Heaving is the upward movement of soil due to wide temperature fluctuations coupled with the expansion and contraction of moisture (water) within the soil. 

The tiny root hairs of a plant are microscopic and invisible to the human eye. They are responsible for absorbing water and nutrients for the plant. The freezing and thawing process of heaving, negatively affects these tiny hair roots, resulting in damage or even death to a plant. And at times, if the plant was not properly planted, heaving can push the plant up from the ground exposing its roots to other damaging environmental conditions, such as insects, diseases, and animals.

To minimize heat loss in the soil surrounding the plant, and the potential for heaving, winterize your plants with shredded wood mulch. Shredded leaves also provide a good source of organic mulch, as well as pine needles. Four to six inches of mulch will help the soil temperature remain consistent and help prevent heaving.

Other helpful considerations for Minnesota gardeners include:

1. Select plants according to the USDA Plant Hardiness Zone map.

2. Watch “Right Plant Right Place” video series on the U of MN Extension You Tube channel to learn how to give your plants the best start possible.

3. Continue to water your plants until the ground freezes. Water serves as an insulator; well-watered soil retains heat. And as your plants come to life in the spring, they’ll get their first drink of water as the ground thaws.

4. And if possible, mulch after the top one to two inches of the ground has frozen. The mulch helps retain moisture from watering.

In summary, to prevent potential root injury, Weisenhorn says, “Snow cover and mulch are good insulators and help keep soil temperatures warmer . . . Soil moisture is important to root and plant health.”

So, the big question on many people’s minds is, “Will we get snow this winter or see a repeat performance of the Lost Winter of 2023-2024?”  “Hard to say what exactly will happen for the winter of 2024 -‘25, but it would be difficult to have a repeat of the record warmth and the nearly snowless winter of 2023-’24,” says Assistant State Climatologist Pete Boulay, MN DNR. “The Winter Outlook (December-February) from the Climate Prediction Center depicts a slight tendency for below normal temperatures over Northwest Minnesota with equal chances of below normal and above normal temperatures across the rest of the state. There is a slight tilt for above normal precipitation across the eastern half of the state. La Niña is expected to be present this winter. For me, I prepare for the worst and hope for the best!”

We can’t control the weather, but we can in part, minimize the effects it has on our plants with proper planning and preparation. Whether it snows or not this coming winter, let’s plant and maintain properly, water sufficiently and mulch so your plants will have a blooming tomorrow. Make sure your plants will be the “Happy Perennials of spring 2025.”

To read more on The Lost Winter of 2023-’24, log on to https://www.dnr.state.mn.us/climate/journal/lost-winter-2023-24.html.

To learn more about the intricacies of a plant root system, log on to https://open.lib.umn.edu/horticulture/chapter/3-3-roots/.

For fun facts about Minnesota weather, log on to https://www.dnr.state.mn.us/climate/summaries_and_publications/normalsportal.html.

https://www.youtube.com/watch?v=PkaBGry87JE&list=PLyMOSdo2sM9sqq7P8DR8qKV8f_bkPXAgG&index=1

*https://extension.umn.edu/yard-and-garden-news/winterizing-plants-cold-damage

Photo Credit: https://open.lib.umn.edu/horticulture/chapter/3-3-roots/ (1), University of Minnesota Extension (2), Patricia Johnson (3)