Near record low temps may impact grass, plants, fruit

Author: Cory Reppenhagen Published: 9:57 PM MDT April 9, 2020

DENVER — A winter storm in April is not uncommon in Colorado, but the temperatures with the next storm will be unusually cold.

Denver’s all-time record low temperature for April 13 is 17°. The current forecast for Monday is 17°. Tuesday and Wednesday could be just as cold. Denver’s record low for those days is 15° and 18° respectively. 

That is bad news for some of those cherry, plum, peach, and other stone fruit trees that have blossoms already open.

If there’s anything in full flower, it will probably kill those blossoms,” said Tony Hahn, a horticulturist with Denver Commercial Property Services.

Fortunately, there are not as many open blossoms noticeable along the Front Range as there often are by the second week of April. The photo below shows cherry blossoms in full bloom in Denver in March of 2017.


Cherry Blossoms in full bloom in downtown Denver on March 26, 2017 – KUSA

Hahn said the blossoms have a better chance if the buds are still tucked in.

And for those who like to spread grass seed ahead of spring snows, Hahn said the seed will survive the cold as long as they’re not exposed on top of the soil.  But he said not to expect any action for a while.

“Seed germination, grass seed germination depends on soil temperature to a great degree, and our soil temperatures are just not there yet,” said Hahn.

He said it might be early May before soil temps reach the preferred 60 degrees for seed germination this year.

As for spring veggies like lettuce, carrots, broccoli, and spinach, Hahn said they are cold-tough and might survived uncovered, but it helps to have cold frames or some sort of cover. Just try not to let the material that you cover them with come in contact with the plants.

Cold Frame | Tiffany Reppenhagen

Cold frames for your plants can be easily made with half-inch PVC piping and a thin plastic tarp. These will double as hail protection because they can be quickly assembled when a storm pops up.

Veggies safe and warm under a cold frame hut
Tiffany Reppenhagen

As for the snow that will come before the cold, Hahn said that’s actually a good thing.

“Yeah absolutely. I was hoping we were going to get some snow first to kind of insulate things,” said Hahn. ” If we get a couple inches of snow, that’s a great insulator, and it will protect those tender plants and seedlings from the really cold temperatures.”

Hahn said that he hasn’t seen too many residential sprinkler systems back up and running yet. There has not been a more than two week period without some sort of moisture on the Front Range in more than 30 days. 

But if you did turn them on already, make sure to cover the back-flow preventer before Monday morning, as any above-ground parts will be susceptible to freeze. 

He said that if we get a half-inch to an inch of water from the snow in this next storm cycle, that should take us all the way into May without having to water our trees and lawns. 

After the next one week stretch without moisture in May is when we should turn our sprinkler systems back on.

Watch on 9News Contact Tony

About Denver Commercial Property Services

Denver Commercial Property Services (DCPS) provides commercial property services to 1,100+ clients across Colorado. DCPS leverages unparalleled customer service to be the dominant, one-stop provider of commercial property services in Colorado.


Natalie Clark, Marketing Director