Seven Ways to Protect Your Fragile Plants from Frost
If you don’t live in
an area where it is frost-free year-round, you need to plan for your plants for wintertime, states Tammy Sons, a gardener at Tn Nursery.
Frost and hard freezes
are detrimental, usually deadly, for most plants. Frost is traditionally
categorized one of two ways:
- Light frost. Light frosts occur between 28°F to 32°F
(-2.2°C to 0°C). This type of frost is difficult for fragile plants,
though sometimes survivable.
- Hard frost. Hard frosts are 28°F (-2.2°C) or colder,
and they are usually deadly for most plants, whether they are fragile or
not.
Why is Frost Harmful to Plants?
Frost and freezing injuries plants because plants are mostly
water; plants can be up to 95% water.
When the water inside
plants turns to ice crystals, the tissue is damaged, and the movement of fluids
and nutrients within the plant is disrupted or completely halted.
Water Plants in the Afternoon
This is less about
hydrating the plant and more about moistening the surrounding soil around it.
Wet soil has an insulating
effect, meaning that heat from the ground will radiate upwards to the plant
overnight when the temperatures are most likely to drop.
Add a Layer of Mulch to the Plant
Thick
mulch to a plant is what a heavy quilt is to a person. Use mulch to insulate the plant. The best
method is bagged mulch, sawdust, woodchips, straw, grass clippings, or even
leaves as protective mulch. Add three to six inches of your mulch around each
plant and leave one to two inches of space between the plant’s main stem and
the mulch. This allows the earth’s warmth to slowly radiate up past the fragile
plant as the temperatures drop.
When the weather
begins to warm, pull some of the mulch away.
Use a Cloche to Cover the Plant
A cloche is like a
miniature greenhouse.
It is a bell-shaped
cover that is somewhat or entirely transparent, made of plastic or glass, and
intended to retain heat or humidity for individual plants.
You may purchase
cloches online or from your local nursery. You may also make some at home using
regular household items.
You can repurpose
buckets, flowerpots, cups, and jars into cloches. Many people prefer plastic
jugs and bottles as cloches because the cap can be added or removed as needed
for heat and humidity fluctuations. Milk jugs and pop bottles with the bottoms
cut out are also practical.
For maximum effect,
screw the cap on tightly, add to the plant just before dusk, and nestle the
bottom of the cloche firmly into the soil. Be sure to uncover the plant at dawn
so the plant can soak up the sunshine and warmth of the morning right away.
Use Rocks and Bricks as Miniature Heaters
During the warmest
part of the day, place a rock, brick, or chunk of concrete beside your plant.
While it is sunny and
warm, it will absorb heat. Slowly overnight, it will release the heat. If you
place it next to your plant, it can act as a small heater.
If you really want the
maximum effect, utilize a warming rock and a cloche. Allow the stone to heat up
in direct sunlight all day, and then cover the rock and the plant with the
cloche right at nightfall.
Blanket Your Fragile Plants
For plants that need
protection from winter freezes, consider using burlap, blankets, towels, or
drop cloths. The blanket method is like the cloche method but on a bigger
scale.
Create a tent-like
structure using t-posts, tomato cages, stakes, or even chairs so that the
material doesn’t crush the plants. Make sure your fabric drapes all the way to
the ground, and don’t tie it to the trees or plants. The earth’s heat to
radiate through the plant and hover within the tent-like structure you created.
Weigh the edge down
with rocks or stake it down so it doesn’t blow away overnight.
For additional frost
resistance, you may add a shower liner, a sheet of plastic, or a tarp to the
top of the blanket.
Ensure that no part of
the plastic touches your plants as it can harm the foliage.
Just like the cloche,
add the blanket right before dusk, and remove it again at dawn.
Use Fans
This tip seems
counterintuitive, but I assure you, it is effective. The secret is that the
constant airflow blows away lingering precipitation that may lead to damaging
ice or frost.
Surprisingly enough,
simulating wind can raise the temperature of your garden patch by anywhere from
2°F to 7°F degrees.
Bring (or Keep) Your Plants in a Temperature Controlled Building
A greenhouse is the
absolute best way to protect and overwinter even the most fragile plants.
Greenhouses retain
heat from the sun naturally. They can also have electric heaters, woodstoves,
or geothermal heat sources installed into them as well. Greenhouses come in
various sizes and can range from tiny three-square feet all the way up to
two-hundred thousand square feet. There are thousands of options and price
points to choose from.
If a greenhouse isn’t
feasible for you, consider keeping your beloved fragile plants in pots. When
the weather drops, you may bring them inside your home to protect them from the
brutal cold.
If you plan on taking
your plants in and out of your home, consider using a preventative anti-bug
measure such as neem oil. Neem oil acts as an insecticide and a miticide, which
will protect you, your home, and your other indoor plants from pests.
