You Can Laugh At Frigid Temps and Polar Vortexes – If You Follow This Plan

Cover tender plants with a sheet of 4 mil plastic.

Cover tender plants with a sheet of 4 mil plastic.

Two polar vortex systems have passed into middle Tennessee in January 2014. So what?

There will be dead plants apparent in a couple weeks? Why?

They weren’t cold hardy, meaning they weren’t adapted to the cold climate in first place. Or…

They were planted incorrectly. Or…

They were dry. Why should this matter?

Dry roots mean that the stems are more likely to dessicate or dry out from the frigid winds.

The next time it’s going to be below 32 degrees, make sure your plants in containers or freshly planted trees and shrubs are soaked.

The ice crystals that form from free water in the soil actually insulate the roots. So says scientists…

Enjoy the warm winter days! Trees and daffodils will be blooming soon…

How to Improve Cold Hardiness and Winter Protection for Landscape Plants

Imagine for a minute, you’re at a garden center… just browsing.

Cover tender plants with a sheet of 4 mil plastic.

Cover tender plants with a sheet of 4 mil plastic.

It’s the middle of Spring and a confederate Jasmine vine catches your eye.

The small yellow blooms are attractive and you instantly know the perfect spot for it at home.

A garden center employee mentions to you “It grows like a weed, but might not be cold hardy”, she says.  You make the purchase anyway because it’s gorgeous and take it home.

One look at the plant tag says it’s a Zone 8 plant. What does this mean and where should I plant it?

Cold Hardiness Zone

Cold hardiness is the rating a plant receives to indicate how cold a temperature it can withstand before damage. The USDA developed the Cold Hardiness Zone Map. Find your zone. Click here.

For Tennessee, Zone 8 is the warmest zone. Zone 8 is located near Memphis. This means that the cold weather typically doesn’t fall below zero degrees Fahrenheit. But it’s not a sure thing.

Cold hardiness zones are based on temperature averages over the previous decades. It’s well known the North-Western Hemisphere is in a slight warming trend, but each year the temperature could swing near record lows.

Zone 6 is the coldest climate in Tennessee, located in the eastern part of the state.

What is the best planting location for tender plants?
  • Plant susceptible tender plants on the southern side of the home and as close to the foundation as possible.

The heat from the home will radiate to the root system in the Winter. If the root system survives, the plant will flush new fresh growth in Spring. If the southern side and home foundation are not available, avoid a windy alley. Frigid cold wind causes dessication, or drying out of plant stems.

What Does Winter Damage Look Like?
  • Dessication damage may occur with stem splitting or stem die back.

Hard pruning is required to remove the dead stems. This may or may not be acceptable to you. Removing the dead stems will allow to the plant to flush new growth the following Spring. The new growth will hide the stem stumps.

Another way to protect susceptible plants is to wrap them in burlap or plastic. This traps humidity and warmer air. It helps eliminate dessication. For more info, click here.

How Do I Minimize the Possibility of Damage?
  • Purchase and Install cold hardy trees and shrubs.

That means if you’re in a Zone 6, 7, or 8, use trees and shrubs with a cold hardiness of 3, 4, and 5. These plants are extremely resistant to cold damage. A great hardy shrub is hydrangea.

Do you have any more tips that I didn’t mention? Please continue the conversation on the Facebook page.

How to Protect Tender and New Plants from Sub-Freezing Temperatures and Frigid Cold Wind

 

The bed sheet and plastic trap ground heat and act as a greenhouse.

The bed sheet and plastic trap ground heat and act as a greenhouse.

It’s not complicated.

Just make a tiny greenhouse!

Lock in the Moisture

Start with a piece of burlap or sheet plastic. A square shape that isn’t too big and bulky is a plus. Wrap the plant tightly with clothes pins, string, or bungee cords. The tighter the better.

If the plant roots are inside a container, like a clay pot on a patio, lay the plant sideways so it’s closer to the ground. Cover the container and plant with plastic or a bedsheet. This protects the roots by trapping the small amount of heat coming from the ground. The ground temperature is higher than the cold air and the plastic or covering will trap the heat like a greenhouse.

After the temperature rises above 32 degrees Fahrenheit and remains so, remove the covering. The plant most likely will survive this cold snap and get stronger next year.

This Winter protection isn’t necessary if the tree or shrub is planted in the ground and is cold hardy. Cold hardy is determined by a zone number. Most plants in your area are cold hardy. This means their cold hardiness zone is equal to your climate zone or colder. For Tennessee, that’s zone 6, 7, and 8.

Find your cold hardiness zone here.