Dealing with Frost Damage

Friday, May 19, 2017 // Oh, Mother Nature, you are one tricky lady! A few weeks ago, you enchanted us with a string of beautiful days of sunshine and warm weather, leading us to believe Spring had really sprung. Our thoughts turned to getting outside and beautifying our surroundings. Everywhere we went, vibrantly colored flowers and lush greenery called out to us. We were itching to get our hands in the dirt. We wanted to leave Old Man Winter behind and grow things. The calendar even told us it was ok - Spring had officially begun. Our perennials started to come back to life and our bulbs began poking through the soil. We even put some of our container plants outside to soak up the sun. That’s when it happened, that reminder that yes, we do live in Michigan. The state where on Monday it’s sunny and 75 degrees, and on Tuesday morning we wake up to frost on the ground. Our plants were downright shocked, and they are clearly showing the after effects of this cold snap. What can and should be done to bring them back to life?

First things first, what happens to your plants when there is a frost? When the temps hit around 32 degrees, water vapor freezes on the surface of plants which creates that frosted appearance. If the temperature dips below 32 degrees, water inside and outside plant cells freeze. The ice within the plant punctures the plant’s cells and will cause that part of the plant to die. A sure sign of frost damage? Wilting of the outer leaves. That wilted growth will turn brown and crispy, indicating that part of the plant has died. The idea here is to keep calm and carry on. Though you may be tempted to try anything to get your plants healthy and green again, less is more. A few tips:

  • Watering is recommended, as it helps plants overcome shock and provides nourishment for healing and growth. However, take care to not over-water.
  • Stay away from fertilizer until you start to see new growth. Nitrogen in fertilizer can make your plants leaf out too quickly, causing more stress.
  • Your first thought may be to get in there and cut out all that brown, crispy foliage. Don’t – you risk doing more damage if you remove it too soon. All that ugliness can help protect the interior of the plant from future frost. Resist heavy pruning until the plant returns to its normal growth pattern. Most plants will begin to show new growth in as little as two to four weeks after frost damage. Intensive pruning too soon will stress the plant further.
  • As hard as it is to do, the best plan of action is to wait and see. Once the threat of frost is truly over, and new growth starts to appear, it’s time to prune. Take note that a branch may have dead leaves due to frost damage, but the branch itself may not be dead. Damage from freezing affects the leaves first, followed by the stems, branches and roots. Live stems and branches will produce new growth, while those killed by frost damage will not. You may think that your entire plant died only to discover new growth occurring toward the base a couple of months after the last frost. It pays to wait it out.
  • How to prune? The methods are different based on the extent of damage to the plant. If only the outer growth has been affected, and the growth underneath has not, lightly prune the damaged stems or branches using hand pruners or loppers. If the majority of the upper growth of a plant was killed by the cold, then renewal pruning is the best way to prune. This involves severely pruning back the affected areas, often to within a few inches of the ground. Loppers and sometimes a pruning saw will be needed. Because the base of a plant and its roots are the least susceptible to injury from freezing temperatures, severely pruned plants will often grow right back.
  • If you left a container or potted plant out in the cold, such as a tropical houseplant, the solution is to bring them inside as soon as possible. Warm them up gradually, as you don’t want to put them in shock by immediately going from extreme cold to too much heat. Start out by placing them in the garage or on a sun porch.  The right combination of water, nutrients, and warmth will help the plant to snap back. The dead foliage will fall off and new growth will appear.

 The best way to avoid plants from freezing and frostbite is to utilize a few preventative measures:

  • Covering plants helps protect them from severe temperatures. You can use inverted plastic pots, old sheets and even plastic to cover vulnerable plants. Remove the coverings when temperatures rise.
  • Mulching helps soil retain water and keep plants warmer.
  • Cluster container plants close together and in a sheltered spot. Near the house is ideal.
  • Plant with the cold weather in mind. Plant less hardy plants in full sun or an area that retains heat, such as under a canopy.
  • Bring your tropical plants inside during the winter. They are too delicate to survive the extreme cold.

As disheartening as it seems, an unexpected frost does not mean the end of a damaged plant. With a little patience, TLC, and the true arrival of warm weather, your plants will bounce back and beautify your landscape for years to come. Take that, Mother Nature!

Check out the plant damage we had in our own landscape recently:


Tags: Landscaping Tips