Can I use lime to control ammonia in my horse’s stall? 


Ammonia is a by product of urine, and you definitely know it when you smell it.  Unfortunately, ammonia is everywhere, and can be hazardous to your horse.  Just think about eating with you nose to the ground, where all of the ammonia is.  For more details on ammonia and how it creates danger to your horse, read this article.  It's tempting to use lime, as many horse folks have used it in the past, so it must be OK.  Turns out, it's anything but OK.  Either the lime variation is USELESS, or it's DOWNRIGHT HARMFUL.




Some of the problems with calcium hydroxide.  Skip it.

You most definitely should NOT use any type of lime around horses.  Lime (in all of it’s various forms) has a giant list of horse unfriendly side effects.  For the most part, the following types of lime are used to chance the pH balance of soil.  There are better options out there for your horse’s stall!  This is what you may find at the feed store/garden center/home improvement store:


  • Calcium carbonate.  This stuff is just called lime, ag lime, daily lime, garden lime.  It’s benign - it won’t burn your horse, or poison your horse.  It’s also a super fine powder that has a way of ending up in your horse’s lungs, made from crushed limestone.  Dust and ammonia are not friendly to your horse’s lungs.  


  • Calcium carbonate also fails to remove ammonia odor, it can only cover it up.  It also becomes as slippery as snot when it’s wet - like when it’s put on urine spots!  





  • Calcium hydroxide.  This is also known as hydrated lime.  It’s also highly dusty, and when it’s wet (from urine or water) it becomes caustic and can cause serious burns on your horse’s skin.  It can also cause eye damage, keeping in mind that eyes don’t grow back.  


  • Perhaps the biggest problem is that calcium hydroxide actually causes more ammonia to be formed.  This totally defeats the purpose!  


Amazing alternatives to lime when dealing with ammonia in stalls are products that are created from minerals. One popular example is zeolite, which is a mineral that specializes in removing other substances from the environment.  Technically it’s a sieve, but I think of it as an ammonia vacuum cleaner. 



A handful of Sweet PDZ from my stash at home - it keeps the kitty litter boxes fresh and the garage dry.

Zeolites are not toxic and actually trap ammonia.  Time to ditch the lime and find something safer!  And for the pocket book…. zeolite products like Sweet PDZ are about 10 cents cheaper per pound than lime.  You can read a novel (not really) about zeolites here. 


What do you use in your horse’s stall to remove ammonia?