12 Tips How To Protect Plants From Frost

Four rosehips covered in frost.

Protecting your plants from the threat of frost and the danger of sudden temperature fluctuations in the coldest months of winter can save them from unexpected devastations.

Tender young plants are too fragile to survive from sudden fluctuation in temperature, and unprotected tender plants that are just growing often die from frost exposure. While shrubs and trees survive from the unexpected freeze, they still lose bulbs or mature fruits.

Frost damage, root damage, and cracks on the barks are all adverse effects of the sudden drops of temperature.

Ice crystals are another type of frost injury. It can form in the plant cells and hinders the water movement in the tissues, causing injuries that are fatal to the plants when ignored.

And leaves turning black or shriveled are the primary symptoms you’ll notice due to frost injury.

12 Ways To Protect Your Plants From Frost

The threat of frost in the late spring or the fall is unpredictable. It happens overnight when the temperature suddenly drops, freezing the moisture in the plant’s leaves and buds.

Unexpected frost can cause devastation making gardeners scramble to find anything to cover new plant growth.

Learn which tip will work best for you and find out how to protect your garden landscape from winter.

But protecting your crops from the freezing temperatures also depends on your location and how cold your winter can get.

1) Move Potted Plants Indoors

Four potted poinsettias Christmas plants.

When the frost is in the forecast, and you’re expecting it in the evening, wait until dusk and move potted plants susceptible to the danger of frost indoors.

Unlike plants grown in-ground who benefit from the insulating power of the surrounding soil during the chilly temperature, the plants grown in containers are more exposed to the cold climates, leaving them more vulnerable to frost injury.

Potted plants left outside are susceptible to root damage in colder temperatures.

Place the plants in a place that is not too warm when you bring them inside. Doing so will avoid the possibility of plant shock due to sudden changes in temperatures.

However, don’t forget to check the plants for pests and diseases before moving them inside. And try to isolate houseplants as the potential spread of pests and diseases can happen quickly.

When the threat of frost passes, move them back outside first thing in the morning to receive an adequate amount of sunlight.

2) Select Frost-Resistant Site

Six recyclable medium size containers and one plastic pot, growing about three to four seedlings each.

Placing your plants in the dark structure facing south or west can provide additional protection against freezing winter.

Dark structures absorb heat during the day and radiate accumulated heat at night, keeping the plants warmer.

Also, place seedlings and small plants in higher spots that are less likely to experience cold air movements.

Chilling air will usually pass by plants located in the higher ground or on slopes, making it the best location for plants that are susceptible to frost damage.

Cold air is heavier and denser than warm air, making low lying areas of the gardens get colder a few degrees than in the higher spots.

3) Add Mulch To Your Plants

Gardeners hand introducing the brown mulch.
Image by: the-journal.com

In winter, a bare ground that encounters a fluctuation in temperature generates unusual movements. And this movement can heave either small or shallow-rooted plants, exposing the roots to damaging winter frost.

Adding a generous layer of mulch to your garden is like slipping a sweater on to protect the soil and the plant’s roots from sudden fluctuations of temperature.

Using mulch like wood chips, straw, or dried leaves can provide insulation for the plant’s roots as it becomes an excellent barrier on the top surface of the soil.

Mulching about three to six inches deep can create an efficient barrier. However, leave an inch around the base of the plants. It will help the plants absorb the warmth of the soil.

Adding mulch to the plants is a less expensive way to protect your plants from the extreme cold of a temperature. But when the weather starts to warm, you’ll want to pull back some of the mulch as it helps warm the soil faster and prepares the ground for planting.

4) Harden-Off Seedlings

Chilli seedling growing on a clay pot placed on the table.

Giving your plants time to acclimate both an outdoor and indoor temperature will likely help them survive in both conditions.

The process of hardening off will help your plants grow robust and withstand temperature change when moving indoors as you protect them from the possibility of frost injury due to sudden freezing.

5) Cover Your Plants

A Bok choy plant covered in a frost fabric protection.
Image by: gardenista.com

To cover your plants with materials like fabric, burlap, plastic, and many others when the temperature drops will keep the moisture from freezing.

Using fabric to cover your plants disperses moisture inside the coverings while protecting from frost.

Fabric covers are breathable, and it prevents direct contact of the freezing air to the plants. Besides, it captures the heat radiating from the ground providing warmth to the plants.

Bedsheets and comforters work best for covering larger plants and shrubs. Make sure the cover reaches the ground to trap the warm air inside the coverings.

Some gardeners use plastic to protect plants from frost. However, make sure the plastic cover does not touch the plants during the winter.

Plastic covers that touch your plants can hold moisture causing fatal freeze damage against plant tissues.

Some gardeners erect stall stakes around frost-sensitive plants to secure plastic covers over the plants. The covers will shield the plants without having to worry about them being blown away in the night or damaging the branches.

Also, covering your plants with generous layers provides better insulation, particularly in the freezing climate.

Feel free to cover your plants with a few extra layers, especially those tender new growth plants during the extreme weather.

But whatever covers you use, remember to uncover the plant when the threat of frost passes. Doing so will prevent heat build-up inside the canopy when the sun comes out.

6) Cloche To Protect Plants

Seven glass cloche in the garden.
Image by: seedsnow.com

Covering your plants with a cloche to protect from an overnight frost will prevent the possibility of the frost injury.

A cloche made of plastic or glass is a small portable covering you can use and move around your garden. Besides, it traps heat from the sun and raises the temperature of both the soil and air inside.

A DIY milk jug gallon with its bottom cut out is one of the most common cloches used by home gardeners to cover a single plant or a small group of plants.

Although the technique is efficient and the materials can be found just around the house, the cloche is not a long term-term solution to protecting plants.

Since the cover is too small, it does not retain sufficient heat to sustain plants for more than a day, particularly when the temperatures fall below 40 degrees Fahrenheit.

And aside from being small, it has no venting unless you lift it from the plants, which can result in an overheated temperature inside the cover.

However, cloches are most helpful in the late spring and early fall when the weather temperature always changes. Using them to protect the plants will help extend your garden’s growing season of about 2 to 4 weeks.

Several types of cloches:

  • Glass bell jars
  • Plastic jugs or large water bottles
  • Portable A-frame or box of rigid plastic structures
  • Arched plastic tunnels
  • Wire mesh cylinder cloche
  • Folded newspapers

Set cloche in place early in the day to capture the heat from the sun. Doing so will warm the air and soil inside.

The rise in temperature inside the cover is enough to protect the plants from the light freeze. And if you intend leaving the cloche in place for longer than a day, allow the cover to vent.

You can remove the cap of a milk jug to vent or lift the covers individually. The task is a bit tiring but helpful enough to protect plants in your gardens. 

7) Lay Garden Blankets

The raised bed garden covered in a frost blanket.
Image by: gardeningknowhow.com

Covering a large group of plants in your garden requires broader covers. Blankets, bedsheets, or drop cloths make suitable covers for vulnerable plants to ensure they are well covered and protected.

There are frost blankets you can get from garden centers too. These are lightweight woven material specifically designed to cover plants in winter.

The blankets protect plants from frost and help provide warmth to the plants by trapping the heat that radiates from the soil.

When the plants receive sunlight, the heat radiates from the soil surface. And without a frost blanket, it disperses into the surrounding air. However, a frost blanket can trap the heat and create a pocket of warm air to keep your plants from freezing.

Frost blankets are inexpensive winter protection that traps heat for your plants. Therefore, it requires venting.

If you intend to use the blanket for about 3 to 4 months, you have to monitor the covers regularly because the development of mold can appear.

8) Wrap Your Shrubs & Trees

Tree branches wrapped in paper rolls.
Image by: fdrfourfreedomspark.org

Extreme cold in winter can damage plants through sunscald, dieback, root injury, and frost heaving. However, there are a few techniques you can use to prevent cold damage.

Sunscald is most common on young trees with thin bark. It happens when the temperature suddenly fluctuates or when the bark heats up on cold winter days, then chills down rapidly when the sun goes down or is blocked with trees and clouds.

Wrapping the bark of susceptible trees with either tree wrap tape, plastic tree guards, or fabric wraps will prevent the possibility of sunscald.

You can either use DIY wraps with burlap and unused fabrics or get some wraps available in garden centers near you.

However, don’t forget to remove the wraps in the late frost of spring to avoid choking as the tree grows and prevents insects from hiding under the materials during summer.

9) Do Not Prune Dead Branches

Dieback is when the parts of the tree, such as twigs and buds, are damaged and killed. And this usually happens to deciduous shrubs or trees that lose leaves in the winter.

When your tree or shrubs get damaged from dieback, do not be in a rush to prune off dead branches. These damaged branches can act as an insulator to prevent further damage.

But sometimes, these branches look dead on the surface, yet living tissues which will produce buds are still underneath.

Wait until mid-spring to prune dieback branches, especially on some variety of roses. Less hardy roses often show dieback in winter.

10) Water Plants Before a Hard Frost

 Water flowering plants with a garden hose.Image by: gardensnursery.com

When the soil temperature falls below 10 degrees Fahrenheit in the winter, root injury can happen. However, due to latent heat in the soil, roots and the soil temperature hardly get this low.

Moist soil does not get cold as much as dry soil. And watering in the fall will help prevent dryness or the possibility of root injury.

Water acts as an insulator in cold weather and protects plants from freezing temperatures. And plants that are plump with water can withstand cold damage.

Also, moist soil stays warmer than dry soil, which is why watering the plants regularly in dry cold weather will help protect the plants from freezing.

11) Turn On Christmas Lights

Christmas lights around the trunk, branches, and star lanterns hanging on a tree.
Image by:christmaslightsetc.com

To give off enough heat to your trees and shrubs in the extreme cold winter, you can string Christmas lights or heat lamps on your plants.

Don’t use new LED lights. It does not generate much heat, not enough to protect your plants from the cold. Use incandescent light as it turns lost electricity into heat.

Concentrate the bulbs around the trunk and in the branches, and as the lights generate heat, it will protect the tree from damage because of cold.

Also, protect your plugs from the rain by cutting some plastic bags and secure exposed sockets inside with electrical tape.

12) Try Anti-Transparent Foliar Sprays

There are anti-transparent foliar sprays you can get at your local nursery. It will help you guard ornamental plants against light frost. The foliage spray is specifically designed to protect plants’ leaves for about a month by sealing in moisture with a light coating of the polymer film.

However, make sure leaves are well sprayed to prevent the possibility of frost damage. Leaves not adequately covered by the spray may still suffer frost damage when the temperature drops below 30 degrees Fahrenheit.

Final Thoughts On How To Protect Plants From Frost

Preparing your garden from the bitter cold before winter begins is a must. You can protect vulnerable seedlings, new transplants, and crops from the damaging winter cold and frost.

Even in mid-winter regions, frost damages happens in many garden favorites such as citrus, succulents, and some ornamental plants. However, a few simple strategies can save your plants from the harm of freezing temperatures.

Paying attention to the weather forecast will allow you to prepare any supplies you can use to protect the plants from the chilly night.

And remember to use lightweight covers to protect your plants. Place them over the crops, trees, or shrubs, ensuring the heat that radiates from the ground is trapped to help prevent the plants from freezing.

Moreover, don’t forget to remove the cover protection in the morning or lift the cloche to vent as the temperature begins to warm during the day.

Doing so might be tiring, but the temperature under the frost cover can build up heat very quickly, making it harmful to tender and new growth plants.

In most cases, you can use simple DIY ideas to protect your plants when the temperature drops in the winter. But for a large vegetable garden, you’ll need the right covering materials to protect your plants against frosty weather. If you have any questions, feel free to ask below!




About Benita Abucejo

Hi there! My name is Benita Abucejo. What can I say? I truly love spending my days in the outdoors, specifically in the garden. Gardening has always been a strong passion of mine since I was a little girl. It has brought me so much joy and happiness that it is definitely safe to say that I will be a gardener for life. For a period of time, I was able to work with people who are into home gardening and I found it to be quite beneficial to my physical health, as well as my mental well-being. Here at Seasonal Preferences, I am going to share with you my experience and ideas so that you can fulfill yourself with the same satisfaction and happiness. Of course, if you have ideas, I would love to hear those as well! Being creative in the garden can really be quite fascinating so let's share our experiences and be the best gardeners we can be. With that being said, thank you for dropping by and please leave me a comment on one of my posts if you would like to get in touch!

View all posts by Benita Abucejo →

Leave a Reply

Your email address will not be published. Required fields are marked *