Is it safe for your horse to eat frosty grass?


When I started to search for answers about letting a horse eat frosty grass, I was expecting to find a lot of things about NSC values, metabolic horses, and horses with brain freeze. What I found was a BUNCH of stuff that relates to colic in horses and also cows. More on the cows later. But colic? Many folks learned, over the years, that frosted grass means colic – OR DOES IT…


Jump to shopping


Colic and frosty grass?


  • Apparently, this is a thing that some of us learned. Turns out, not really true. There’s no reason to think your horse eating some frosty grass will end in a huge vet bill for colic.


  • That being said, he might colic for other reasons. One is that if it’s cold enough for the grass to be frosty and frozen, his water might be, also. Dehydration is a real threat in winter. We know for sure that horses will drink icy water. We also know that horses drink MORE of warm water, so have some warm buckets around. We also know that no drinking = dehydration = colic risk.


  • But frosty grass is cold and yucky and why would he want to eat it? Because he’s a horse, they don’t know climate control and perfectly heated food and air conditioning and warm toasty fires. He’s a horse and he’s hungry and grass is delicious, no matter the temperature. And besides, when frosty grass reaches his tummy, it’s already been defrosted and warmed to an appropriate body temperature.


horse in blanket standing in snow by the fence



So frosty or snow-covered grass is perfectly wonderful and safe, right?


  • UM….not so much for SOME horses. Anytime a grass undergoes some circumstances that threaten its little green life, it panics and starts to hoard sugars in preparation for the grasspocalypse. Case in point, frost and ice. Super cold temps trigger grass to hold onto those NSC’s that are not so good for Insulin Resistant and Cushing’s horses. So if your horse is a bit round, has a metabolic issue, has laminitis now or in the past, skip the frosty grass.


  • But you could put a muzzle on him? You totally could!  There’s little chance of it freezing to your horse’s gorgeous noggin, as his body and breath are much warmer than the grass. Dirt lots and no-grass paddocks with a hay net are another choice.


frosty horse pasture and fence

This pasture is a bit frosty and crisp, but the footing is still good and the sun’s out!


All of that aside – is the footing safe on frosty grass?


  • Frosty grass is one thing, frozen grass on frozen ground is another beast altogether, especially if the ground is not perfectly flat. Frozen waves, hoof prints, and other frozen topography force your horse to balance precariously and dangerously. Use caution if the ground is hard!



frosty grass on snow

Would eating this cause brain freeze? Perhaps? Do the horses care? Perhaps not?


But what about the cows?


  • There is a particular category of grass, from the sorghum genus of grasses. These lovely plants are mainly in Asia, Australia, and India. When they are frosted or frozen, these plants quickly create prussic acid, AKA hydrogen cyanide.


  • An unsuspecting cow or pig will quickly die (within minutes) after eating. Ruminants, like cows, digest their food once, then burp it back up as a cud to chew again. This just releases more toxic hydrogen cyanide.


Still wondering what’s up with your horse?


  • Your best resources here are your vet, equine nutritionist, and local Agricultural Extension service for pasture management advice. Your vet and nutritionist can help with your horse, and your Ag Extension service can help you with what’s in your pasture.



profile view of paint horse in greenguard grazing muzzle

If you use a muzzle on frosty or snowy grass, check it often, just in case. This is a Greenguard Equine muzzle, BTW.

In conclusion!

Don’t panic, rely on the experts in your area, and be smart about grazing during frosty times. Know your horse’s metabolic status and graze accordingly!


go shopping button for horse products

Click these links to shop for horse supplies. As an Amazon Associate, I earn from qualifying purchases, which are not a penny more for you. I couldn’t be more grateful for your support!



Safety break-away halter for grazing muzzles.



The best muzzle in the land. Also in raspberry, blueberry, and black colors.

Use code 15PROEQUINE for a lovely discount!


API 16 Gallon 260 Watt Heated Bucket 16HB


Heated bucket


Bucket warmer




Thank you! 



horse eats frosty grass