Overnight freeze in the Front Range: How to protect your plants after the snowstorm

Posted at 4:51 PM, May 19, 2017
and last updated 2017-05-19 23:40:58-04

DENVER – The last signs of the late winter season may be over, but your plants are still in danger from overnight freezing conditions expected across the Front Range until early Saturday morning.

Temperatures are expected to drop down to 30 degrees by 6 a.m. Saturday, but the Front Range will be at or below freezing temperatures for about four hours – from 4 a.m. to 8 a.m. at the latest, according to First Alert Weather Chief Meteorologist Mike Nelson.

That dip in temperature poses great threat for your plants.

“If it’s going to be really cold outside, I’d rather have snow that none at all,” said Andrea Ayers of Garden Patch nursery.

Ayers said that while new plant buyers may think the snow poses a great risk to plants, it’s actually the freezing temperatures that come after the snow has melted that pose the greater risk to your garden.

“The snow, when it’s deep on top of the plants acts as an insulator,” Ayers said.

She advised homeowners to put frost blankets or even your bed sheets over your plants to protect them from getting cold-shocked.

One thing to avoid at all times? Plastic tarps.

Ayers said using plastic tarps is detrimental to plants, as the plastic acts as a conduit to transmit the cold temperatures to the leaf of the plant that the plastic is touching.

She recommends taking any containers you can find to put over your plants – she even said some people use mixing bowls to cover them.

For smaller, fragile plants, you may want to put some sort of structure over them that is not a blanket or a sheet.

Plastic containers are the way to go, Ayers said adding you should cover fragile plants "within an inch of their life.”

Worried about your pipes as well?

Nelson said you shouldn’t be – your underground pipes and sprinkler system should be fine during the freeze.

But if you’re terribly concerned about them or have exposed pipes on the side of your house, throw a blanket over them tonight.

By the way, Nelson suggests that you shut off your sprinkler system for the next week or so as we have enough moisture to go around. 

After Saturday, we won’t see anymore freezing temperatures until next fall, Nelson said. 

-- What if your plants are already cold-stunned? --

Don’t overreact. This happened to me when I left a window open during the winter and woke up to find my Peace Lily drooping. What did I do? I quickly went to the nearest water sink and tried to “revive it.”

This was the wrong thing to do.

Gardening experts recommend that frostbitten plants be left alone until new growth starts.

Don’t over-water, over-fertilize. Watering a plant before a cold front hits is actually a very bad idea.

Over-watering and over-fertilizing might encourage your plants to produce more growth, which could affect those plants and stun their growth.

Avoid heavy pruning. Don’t be tempted to cut the ugly leaves and wait until the cold weather is over for plants to return to their normal growth. This may take up to a year!

Be patient. If your plant is cold-stunned, gardening experts suggest one thing above all: wait and see. Remove decayed plants, but avoid pruning excessively – with the right amount of water, nutrients and warmth, the plant will come back to life!

-- After the freeze, the warmth returns --

The freezing temperatures are expected to be over by about 8 a.m. Saturday, at which point you’ll want to remove those blankets and containers covering your plants.

If you don’t, you run the risk of causing the plants to over-heart – think of it as the greenhouse effect, but in a really small scale.

Information for this article came from Gardening Know-How and


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