My oldest pieces are troughs and planters, 15 years. They are spread out over the U.S. with friends and relatives. Have a few still with me in zone 6. At least 2 planters in New York state near Nyack zone 5 are still fine. Billie

Hi Donna
You have to ask very specific questions about what type of planter and it's location.
I have yet to see even ONE picture of a tufa planter sitting on the ground in winter filled with snow.
You will see pictures of little pots on decks and mushrooms out in the snow. But if you are thinking of large tufa planters that will remain filled with soil, be covered in snow or touch the ground all winter you may be out of luck.

I have never found a single Tufa planter that has lasted on the ground in a Z5. I believe they are like urban legends. Everyone knows someone who has one but when you try to find proof of it's longevity it's impossible to come by.

But if you think you have it tough I'm in a z3 where 8 inch thick concrete walls get destroyed by ice.:)

My one and only tufa planter I made is app. 15" x 8" and the sides are only 5" high. It has hens and chicks planted in it. It's lasted 3 years in Michigan zone 5 winters, it has always sat on mulch, never direct contact with ground. It was made with a Portland cement, sand and peatmoss combo.
Sheree

I suspect small shallow troughs filled with desert type plantings should beat most freeze thaw situations.
But a bigger trough is going to require careful placement and possibly some protection to survive a winter under the snow. Especially in areas where freeze/thaw is a frequent occurance. Protecting it from freezing to the ground is very important. Drain rock, or possibly a treated wood frame under the trough would help protect it from frost heaves.

thank you everyone, for the responses. how then, do people make fountains, etc? they must drag them inside over winter? would reinforcing with wire frames or rebar help with freeze/thaw stability or is that just for strength? what about the tufa on a cement block wall? wouldn't the different textures freeze/thaw at diiferent rates, and then crack the tufa? donna

I'm in zone 7, and this is the trough I made last Sept. {{gwi:73145}}
We had several ice storms, snow storms, etc. But it's fine so far.
{{gwi:73146}}

"how then, do people make fountains, etc? they must drag them inside over winter?"

I wouldn't even be tempted to invest the energy and materials to make a fountain out of tufa, a product with a finite lifespan. Yes, people do it, but I visualize a real mess when it starts to fall apart. WHEN, not IF.

People who make concrete outdoor fountains drain them (and make sure they STAY drained) before the first freeze hits. And if the concrete wasn't made with care and attention to details, it may not last long, either.

I have the feeling that local climate has a lot to do with the lifespan of hypertufa. Here in the PNW, we get a lot of rain, then sudden freezes. If some water has migrated into the concrete, and then expands when freezing temps hit, the concrete is going to deteriorate. But there are probably places that are dry when the cold temps hit, and there may not be much moisture within the concrete piece itself, and that may promote less cracking and less damage. But that's just my theory.

Someone in CA once said: "You can argue with the laws of physics all you want, but you're going to lose." And that's really the bottom line.

Sue

I've had 'tufa and concrete troughs left outside for 3 years now, left them planted and sitting on the ground. It gets down to -60 here in the winter and no damage, plus the sedums always continue growing in the spring.
I flip my fountain over before the snows come and then set it up again after the snow melts in the spring.

Hi Donna
Most folks in my area cover their birdbaths and fountains with plastic.
It's funny though I have concrete pedestal planter about a foot in diameter with thin 1.5 inch walls that has been outside filled with dirt for as long as I can remember. At least 25 years. I got it 10 years ago.
I plant it with annuals like petunias so it is usually dead and bone dry before the snow flies.
My old inground concrete ponds are crack free after ten years as well. They are drained but still fill with snow and ice every winter. They are in a z5. But they were made extremely strong on a rebar basket.

Tufa on a block wall might survive if in a very dry area where the ground doesn't freeze and heave. The blocks will move, the tufa will not. If you can keep the tufa area dry enough in winter it has a chance.

I always tell my customers to empty and turn their tufa pots upside down in the winter, and they can leave them out. It is fine. When they are spending that kind of money for a piece, it better last. I am in z5 and I keep my containers out all winter. I made one oval pot out of tufa and I made a "sister" pot out of portland and sand. Same thickness, and wintered them over together in the same conditions. The portland and sand pot got a crack, the tufa did not.
Jo

Hi Jo
I can believe a young peat trough being very frost resistant.
I have high peat content bricks that dent but don't break even when thrown full force on concrete.
Peat before it starts to decompose is strong stuff in concrete.