I Tried the “3-5-7 Rule” to Style My Living Room Mantel, and I’m Going to Use It in Every Room

When I lived in New York City, I didn’t really have proper mantel decor. My apartment somehow came with a working fireplace, but the TV needed to be hung over it, which limited what I could place on the mantel itself. I stuck to mainly small, shorter pieces of pottery. 

So when I moved into a 1928 home with a full wall of built-in shelves topped with a major mantel in the living room, I had to up my styling game. I used a few of the same pieces from the city, bought Anthropologie’s social media-famous Primrose Mirror to serve as a focal point, grabbed a couple of candlesticks and candles, and did what I thought would be the cheapest and easiest way to fill the sizeable blank space: I piled on the plants.

Problem is, though, despite how bright this room gets with sun, the stained glass windows don’t let in enough light. My plants started faltering, and I had to relocate them to other spots. Which left me with the same challenge: how to fill a fairly big surface without it seeming too cluttered with bitsy things. And that’s where the “3-5-7 Rule” comes into play, which essentially means styling with odd numbers to create an asymmetric but still visually pleasing arrangement of things. 

Maybe you’ve heard groupings of three can be more visually pleasing to the eye and memorable than perfectly symmetric arrangements. The “3-5-7 Rule” takes that concept and expands it to larger odd numbers, particularly clusters of five and seven. Designers always talk about the dynamism of odd number groupings, but sometimes you need more than just three things to fill a larger surface or area. So five and seven give you a little more wiggle room to work with without going overboard with a multiple of three or another unwieldy larger number. 

Knowing live plants were pretty much off the table, I decided stacks of books and a few more pieces of larger pottery would be the solution. I’d flank the centered Primrose Mirror and long SIN candelabra I use as a sculpture (from my last apartment) with two sets of seven items, so there’s still a bit of balance in all the asymmetry. On the left, I’ve gone with an organic shaped Dumae candle, an H&M Home pot, a thrifted ceramic basket, two stacks of books, a secondhand rattan vase, and a splay of dried hydrangeas from my garden. And on the right, it’s two candlesticks from CB2, a Leanne Ford for Crate & Barrel pitcher, a vintage painting, an old shoe mold, another stack of books, and a Terrain marble pedestal bowl. Both sides have two taller items (the dried flowers and the candlesticks), and everything else hovers at a height that allows the focus to be on the mirror and the beautiful original stained glass windows.

Do I think this setup is perfect by any means? No. I’ll constantly be fiddling with it, swapping things in and out as I acquire new pieces and part with the old. But what I do know is the “3-5-7 Rule” allowed me to fill the space in a way that feels less cluttered than just working with threes — and more dynamically than sticking with only pairs. And I know I’ll be using this rule for vignettes in the rest of my home, since I have way more space to work with now. It gives you a great place to start any arrangement.