Thank you Kim. I have yet to create, draped hypertufa, which I am eager to try and see the end result. But following instruction to cure in bright sunshine, I have been waiting for a spate of sunny days, which are becoming less likely as we are approaching autumn.

Cement can cure in sun or shade. If you have ever seen a new cement patio poured - it could be out in the sun or in the shade. Both ways work. Much bigger project, but the curing process is the same. I have typically allowed my Hypertufa or other cement based projects to "cure" outside in the shade in a sealed garbage bag only because my hose (to keep the pot wet) is on the shady side of the house. Also - Cement should not be allowed to dry - it must be kept wet or damp . See the definition of Curing below-

"Curing is the process in which the concrete is protected from loss
of moisture and kept within a reasonable temperature range. The result of this
process is increased strength and decreased permeability. Curing
is also a key player in mitigating cracks in the concrete, which severely
impacts durability."

Also temps should be above 50o F. Which should not be a problem now!

Thanks Mike, this is very interesting and informative.

What happens if the temperature drops below 50?

If it does not cure properly - the end result may be some cracking in the pot.

My first attempt at hypertufa ---- Made a few pots in my garage one winter and it got cold. Big mistake - all pots looked good for the first few weeks , then eventually cracks formed.

Can Hypertufa planters be left outside during long, harsh winters?

I am in zone 6 - gets pretty cold, and I have many large and small hypertufa containers that I leave out all winter.