Should I cover my plants at 39 degrees

Should I Cover My Plants At 39 Degrees? 

Should I cover my plants at 39 degrees or what is the right time to shield them from frost and freezing temperatures?  This is one of the frequently asked questions by gardeners when the cold season is setting in.  We will look at it today and learn more about how to protect plants from frost.

When the weather reports predict frost and overnight lows that are near freezing, what should you do?  You should remain calm and think ahead instead of panicking about your garden that you love so much. Keep in mind that frost is different from freeze. And, there are several strategies you can use to help protect your plants from frosty temperatures.

Still a blessing in disguise, plants like carrots, parsnips, and beets only get sweeter in flavor after a frost.  To better understand what steps to take when freeze warnings threaten, you need to know the point at which the greenery fades to frost-burned brown.

Should I Cover My Plants At 39 Degrees?

Most plants begin to freeze when temperatures remain at 28 degrees for more than five hours.  Seedlings and their tender leaves often give up when the temperatures go as low as 32-33 degrees F.  Tropical plants can tolerate temperatures as low as 40 degrees F.

Covering Plants At 39 Degrees

At What Temperature Do I Need To Cover My Plants?

Right from the time, the temperatures begin to freeze, be on the lookout.  When the temperature reaches around 28 degrees F for five consecutive hours, protect your plants by covering them with sheets, blankets, towels, cardboard, or a tarp.  Cover the plants before dark to trap them in warm air and don’t allow the coverings to touch the foliage.  Make sure you anchor your coverings in case the winds threaten.

Remove the coverings in the morning when the temperatures rise and the frost dissipates.  The heat from the sun can build under the solid coverings killing the plants from high temperatures.

The Right Steps To Follow If You Choose To Cover Your Plants At 39 Degrees Or Lower

Know Your Frost Dates

This is the first most important thing to know.  Keep in mind the first and last frost date.  As the temperatures begin to cool down, the first day of the year that a frost occurs is considered the first frost day.

As the temperatures begin to cool, a week or two later, the first freeze date of the year sets in.  This is what kills most plants.  Due to climate change, these dates will not always be the same, you will have to wait and see what dates the frost is appearing each year.

Know Your Frost Dates

As spring approaches, the temperatures begin to warm up.  On the last day of the year, you can expect a frost is an average last frost date.

Always be diligent to check the weather report regularly or set up a weather app alert to keep an eye on the overnight lows.

Assess The Frost

Don’t just check the beginning of low temperatures but check also the length of time they remain at a low or freezing point.  It is true that lower temperatures damage plants but very cold temperatures that last several hours are much harder on a plant than an hour or less of low freezing temperatures.

Keep in mind that along with evaluating the weather report; know how long the temperatures remain at the same point.  There are also important things you need to find out as shown below

  • Frost Advisory – This is the period when the temperatures are expected to fall up to 36 degrees to 32 degrees Fahrenheit.

  • Freeze Warning – This is a warning issued when there is an 80% chance that the temperatures will hit 32 degrees Fahrenheit or lower.

  • Light Freeze – This is around 29 to 32 degrees Fahrenheit and will kill tender plants.

  • Moderate Freeze – It is around 25to 28 degrees Fahrenheit and widely destructive to most vegetation.

  • Severe Or Hard Freeze – This is from 25 degrees Fahrenheit and colder causing heavy damage to most plants.

Valibe Plant Covers Freeze Protection 10 ft x 30 ft

Assess The Plants And Prioritize

Some plants in your garden are considered hardy as they handle a light frost.  However, those tender ones will be injured or die from freezing temperatures.

Hardy plants will do fine even without protection from the frost.  The plants you should prioritize are the ones with tender leaves to protect them before frost harms them.

Prioritize your time, energy, and money meaning the plants that are most valuable to you should be covered first.  Cover plants that are about to mature first so you don’t lose the harvest.  You have worked so hard to grow those plants, you deserve a good harvest.

What Actions To Take Besides Cover Your Plants At 39 Degrees?

  • Water Your Plants.  If you never knew, water acts as an insulator.  Plant cells that are plump with water can withstand the cold damage easily.  In addition, moist soils tend to stay warmer than dry soil.  Give your plants a good soaking before freezing temperatures set in to help protect your plants.

  • Cover Your Plants.  The soil is a great insulator and thermal regulator that’s why the root vegetables can handle a couple of frosts.  Cover tender plants with commercial frost cloths to protect your plants.  Old bed sheets, tarps, burlap, or even plastic buckets placed over baby plants in early spring can protect plants from frost. Be sure to stake the material down so the wind doesn’t blow it off.  The cover should go all the way to the ground in order to maximize insulation and keep the heat from the soil close to the plants.

    • Note:  If you use a plastic sheet, keep it from touching any foliage or fruit. It is possible for the cold to transfer through the plastic and burn the plant. For small plants, you can cover them with an inverted bucket or flower pot.  Remember to remove the cover when temperatures rise during the day.

  • Harvest Early.  If your plants are nearing harvesting, you can go ahead and harvest them. Most vegetables and fruits will ripen at home after being harvested. Tomatoes, apples, peaches, pears, etc. will continue to ripen off the plant. Once y9ou harvest them, place them in a paper bag in a dark, cool part of your house and check on it a couple of times a week. Enjoy your fruits and vegetables as they ripen and always remove anything that is moldy or rotting.

What Temperature To Cover Plants Conclusion

To avoid facing the devastating effects of frost, you can choose to plant early.  Even if you are ready to cover your plants at 39 degrees or less, you can avoid all the work that comes with covering.  This way you will avoid facing the frost and harvest your crops in good time.

Good Luck!