Frost Risk versus Freeze Risk

Gesila(MI Z5)May 3, 2011

I just checked the weather report for my area and there are no frost risks for the next 10 days. However, there is a moderate freeze risk for tonight (35 degrees) and a low freeze risk for tomorrow night.

What is the difference between frost and freeze?

I have several hostas in pots throughout the garden. Should I bring them in?

Thank you for reporting this comment. Undo
hosta_freak(z6 NC)

We are way past our frost risk here in NC. Freeze risk can be worse because just covering them with something,doesn't stop them from freezing. In my case,I have found that my hostas can survive freeze risks down to 32,sometimes 31 degrees with no damage. Frost risk can be averted just by covering with cardboard boxes,to keep the frost off the leaves,but uncovered,can damage leaves pretty bad. That's what I have found over the years. Phil

    Bookmark   May 3, 2011 at 11:47AM
Thank you for reporting this comment. Undo
ken_adrian Adrian MI cold Z5


you are delusional .. if you think a weatherman can predict.. with any certainty ... 10 days out for frost or freeze ...

you better be checking every night right after dinner ...

both cause cold damage... its just a matter of degree ...

we have seen many recent pix with superficial damage to a leaf or two .. that is frost... superficial ...

freeze ... the entire plant is turned into a heap of gelatinous goo [think a lettuce head left int eh fridge for a month] ... and basically dies back to the crown .. or ground level ... and must regenerate the plant from dormant buds ...

make sense .. or should i try again ...

ANYTHING ... to cover .. and keep the cold off the leaf will protect... not only does it trap soil heat.. but also warms the plant ever so slightly ... a sheet ... paper.. a box .. bucket.. pot.. pan.. anything.. that wont blow away..


ps: any time a freeze is predicted .. it starts with a light frost which keeps on building to the freeze .... so to suggest that you have a potential freeze but no frost.. is a weatherman doing you a disfavor ...

    Bookmark   May 3, 2011 at 12:03PM
Thank you for reporting this comment. Undo

Whether you get a frost or a freeze is mostly based on the dew point, or the water holding capacity of the air. If you get cold, dry air there is a greater chance that things will freeze. This is the worst scenario you can get. If the dew point is near the freezing mark there is a greater likelihood of frost as it gets cold, but the air may not actually get below freezing and then you get a frost buildup on surfaces, but not a freeze.

I suspect that the dew point in your area will be pretty low tonight, so there is a chance of getting a freeze without seeing any actual frost - hence a freeze advisory rather than a frost advisory. Yes, it can freeze without actually getting frost.

    Bookmark   May 3, 2011 at 2:48PM
Thank you for reporting this comment. Undo
Gesila(MI Z5)


We own an ice cream store, so I check the weather every morning. I also do a 10 day forecast once a week when putting together my schedule for employees.

So today, I while on, I noticed that they had a gardening guide and pulled it up. That's where I saw the frost and freeze risk. Logically, I thought that a frost would occur before a freeze and was confused. But, being an inexperienced gardener I thought maybe there was something that I was missing.

I should have known better, I can forecast the rain better here in Western Michigan than they can. Just pull the radar up, check the wind direction, and watch the clouds come over Lake Michigan.

Thanks for your input.


    Bookmark   May 3, 2011 at 2:54PM
Thank you for reporting this comment. Undo
ken_adrian Adrian MI cold Z5

so I check the weather every morning.

===>>> morning will be too late.. to protect them.. i think you are going to have to start checking temps and dew point AFTER DINNER ...


    Bookmark   May 3, 2011 at 3:14PM
Thank you for reporting this comment. Undo
kentstar(5b, NE Ohio)

Throw an old blanket, sheet or even an overturned pot on them if there's a frost warning. We may face that tonight too. Yikes! Will winter never quit?

I for once am glad mine aren't opened up with their leaves yet. But ther is still risks with curled up ones too I guess.

Reminds me, maybe I'd better check our weather forcast for tonight! :)

    Bookmark   May 3, 2011 at 4:27PM
Thank you for reporting this comment. Undo
bernd ny zone5

I am only in zone 5a, but Liberty is starting to unfurl, that might not be able to take any frost. The old ones like Royal Standard and Albomarginata probably can handle that.

It seems that early hostas are out of synch with experience and ask for damage. For the last 40 years the rule in West and Upstate NY by neighbors and relatives was not to plant any tender vegetables before Memorial Day. We always went then to nurseries to buy the tomato and pepper plants. One neighbor one year had to buy those three times, got frozen twice because he thought May 15 would be OK.

Last year 3 frost came here the week of May 11, possibly again this year because the historical potential is there! That would be a week from now. I should have saved all the large boxes, instead of recycling, need to look for old blankets! Those large paperbags for yard waste recycling will be good, would need to cut them in half.....

    Bookmark   May 4, 2011 at 5:03PM
Sign Up to comment
More Discussions
When could I remove the covers from the 2 ceramic pots of mini hostas?
The in-ground hostas are still very much in dormancy....
Esther-B, Zone 7b
Hosta Smart Phone App
I think I have my hubby convinced to write me a smart...
Private email to a poster
Now you CAN privately e-mail a I just now...
Babka NorCal 9b
mulch around hostas. leaves, etc.
I have always read that you need to clean up the hostas...
This will be my first year planting hostas so you could...
Sponsored Products
PLC Lighting Outdoor Lighting. 1-Light Outdoor Bronze Wall Sconce with Frost Gla
$75.89 | Home Depot
Aurora Satin Nickel Three-Light Bath Light with Frosted Glass
$149.00 | Bellacor
Sedona Bronze 2-light Flush Mount Ceiling Fixture
Antique Brass Essex Single Formal Sconce
$293.90 | Bellacor
Aurora Wall Sconce by Maxim Lighting
$50.00 | Lumens
16-1/2" Frosted White Glass Vessel Sink
Square Frosted Crystal Black Cotton Ball Jar with Chrome Cover
Tao Wild Mustang
$15.95 | TileBar
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™