Hello,
I have an old chimenea that I'd like to plant up. It is in a full sun position and obviously gets extremely hot. Are there any plants that would tolerate this kind of heat, over 100° in summer ?

What do you want to grow? Flowers? Vegetables? Herbs?

Hens and chicks and sedums would looks great in there and can tolerate the heat. Cacti as well.

What an interesting planter that would make.
We have a member hear that grows sempervivum in roasting pans, in 100 degree weather. @MelissaHopper
I agree, cactus would do well.

I would go with cactus. I live in Texas and semps fry in the summer heat. If the pot can shade them then it may work.

Oh Lynn, you are making me blush. Last summer I figured out that I was not only growing my semps in metal roasting pans but I was also FRYING them in the same. I had metal roasting pans, sitting on pieces of slate that were embedded in gravel and were the hottest part of the yard. I was quite literaly FRYING my poor semps.

Oh no, were you able to save them Melissa?

Yes I was. I finally got smart and moved them to another location and they recovered. Funny but the plants in the same location that were in ceramic and clay pots did just fine.

Do you know what material were the pans? Copper, Aluminum, Cast Iron or Stainless Steel?

Also your ceramic and clay pots had thin or thick walls?
By thick I mean at least 1/2", although it is not easy to tell as usually the rims of pots are always thicker than the walls.

I am not sure what they are made of. They are mostly old fashioned turkey roasters. I do have some that are definitely aluminum. The pots have fairly thick walls.