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Protecting Plant Health During Winter Dormancy

As the crisp and golden days of Autumn grow shorter and Winter blows in plants will begin to wither up and appear to be dying. As night temperatures plummet, the ground will freeze, and in some areas of the country become blanketed with snow. When the perennial plants above ground stop flourishing and begin to wither during the dormant season of Winter, there’s something extremely vital to plant health that’s happening below the frozen ground surface.

This period of Winter dormancy is when plant roots begin preparing the plant’s soft tissues for freezing temperatures to survive the harsh Winter until more favorable growing conditions arrive in the Spring. Plant roots stop exerting energy to grow new foliage above ground during Winter dormancy, and are now conserving that energy to strengthen plant health until warmer weather returns.

During this dormant period, plant roots beneath the ground surface continue to develop and thrive, maintaining cell membranes as proteins are broken down and remade to strengthen plant health for the Spring growing season. But in order for plant roots to thrive and nourish plants, moisture is needed deep beneath the ground surface. If plant roots are deprived of hydration during this time, nutrients from surrounding soils cannot be absorbed for plant health come Spring. 

Water actually warms the soil, so will insulate plant roots and thereby protect plant health. On the other hand, frozen dry soils will actually freeze plant roots and cause damage. 

Although moisture is needed deep in the root zone during Winter dormancy, landscapes and perennial plants should never be overwatered. Soggy soils will cause root damage due to lack of oxygen, and also promote fungal and bacterial growth.

To help protect plants above ground from heavy wind, winter frosts and icy rain, the following can be done:

  • Apply a layer of hay or mulch around plants to help hold in moisture and heat to protect root systems.
  • Use a plant protecting, breathable blanket to cover plants at night to protect against frost or freezing rain.

In order to deliver the proper amount of moisture to root zones beneath the ground surface during Winter dormancy, it’s necessary to know just how moist or dry the soil is where the eye can’t see. Like a thermostat for your landscape, Soil Moisture Sensors can measure soil moisture levels in the root zone of the plant by sending a high frequency pulse of electricity down an embedded wire path. When the pulse travels through moisture in the surrounding soil, it slows down, measures the speed, and converts the measurement to a moisture content reading. Soil moisture readings are within ±3% of the actual volumetric soil moisture content. These ultra-sensitive sensors are capable of measuring soil moisture changes of less than 0.1%.

When Spring comes milder temperatures and more sunlight will encourage perennials to flourish and grow again. Until then, Winter dormancy provides a much-needed period of rest as root systems continue to develop below ground, exerting energy to protect and nourish plant health above ground in preparation for Spring.