If you’re like me, and you’ve spent way too much time investigating why there is a pervasive smell of cat urine in your yard, the source might surprise you (and you can fix it).
First things first: there’s always a chance that the cat urine smell you smell in your yard or wafting through your windows is, in fact, cat urine. Especially if you have indoor cats, there may be outdoor cats marking your home. But if the smell isn’t just one pungent moment in time but a low-grade smell of cat urine that seems to persist well through the spring and summer, then you can safely stop blaming the random stray.
Instead, you should blame the boxwoods. While there are a variety of ornamental landscaping trees, shrubs, and plants that have varying less-than-pleasant smells, the boxwood is the likely culprit in your yard. Not only is the acrid and persistent cat urine smell unique to the plant, but boxwoods are practically ubiquitous in landscaping throughout much of America, Europe, and beyond. While walking the dog the other evening, I did a rough tally of the homes in my neighborhood that had boxwoods planted in the yard. Over 90% of them did—most of them planted, unfortunately, under the windows.
It’s a shame because boxwoods are lovely in landscaping. They’re a rich glossy green, they’re easy to shape into everything from simple spheres and cubes to complex topiaries, and it’s tough to beat them for the relatively inexpensive visual weight they add to your landscaping. It’s hard even to imagine a formal English garden without boxwood everywhere.
Alas, I’ll be ripping mine out because I don’t want to spend another year where every time I open the windows I think “Why does it smell so much like cat piss in here?”
Finally, I’ll forewarn you: despite the claims of landscapers and garden supply shops that there are no-odor or low-odor boxwoods, there are not. The boxwoods planted outside my windows are specifically a cultivar, Buxus microphylla var. japonica, commonly called Winter Gem boxwood on account of how vibrant it says over the winter. It is frequently cited, along with the Wintergreen variant, as the perfect boxwood to plant to avoid the cat urine smell.
I can assure you, it is not.