Nick,
Looks like we cross posted!
Thanks! I find that most people prefer the shaded grey coloring, though it helps to have a variety of colors so people can pick a favorite. I also find that the white and blue coloring of the piece below does well.

My kiln's internal chamber is octogonal and measures 22" x 18". It is an electric and I fire once slowly to temper the clay over three days, then I add the shading and fire once more for a single day to 2232 degrees Fahrenheit. At that heat, the pores of the clay seal up and it hardens to a strength and density that prevents winter freeze damage from being a problem. I want my pots to be as winter hardy as the succulents I use in them.
Occasionally if invited by fellow potters, I will fire in wood or soda kilns, they also cook to high temperatures and add a nice surface texture to the work.
I have several different sculpting styles at work, even within an individual planter. I have found that combining pinch pots with coils and slab work can really add dimension to the piece, and often using only one of these methods can be restricting.
The materials that I use differ depending on the pot. The white and blue is porcelain with a cobalt oxide wash, shaded grey is a stoneware with a balance of cobalt/iron oxide wash, and the shaded brown colors are one of three darker terracottas/red stonewares with an iron/rutile oxide wash, I also do yellows like the one below with a buff colored stoneware and a chrome/rutile/iron oxide wash.

For all of them I paint on the oxide wash with a brush then wipe it back into the recesses using a damp sponge. For special pieces I will use glaze in a similar fashion.
Once I've completed my final firing, the bases of the pieces are lightly sanded. Then I set about mixing a quick draining soil and plant them using tweezers and rooted cuttings from my garden.

-Sol Zimmerdahl

Sol ~

Thanks so much for the insight of a master at work!

Wood kilns I'm somewhat familiar with, but never heard of soda kilns. Could you explain briefly what a soda kiln is, and how it works?

> Nick

Nick,
Like a wood fire kiln, soda or "salt" fire kilns are heavily atmospheric. Salt (or cleaner burning soda) minerals are added to the firing which is, as I understand, otherwise essentially a reduction firing. These kilns are similar to wood fire kilns because the soda fluxes at high temperatures and creates a natural glaze that covers everything in the kiln as wood ash does in a wood kiln. The natural glaze in soda firings tends to be less viscous than an average wood firing, but both can vary quite a bit depending on the kiln, or fuel used.
While wood firing anagama kilns are actually derivatives of ancient Korea, Salt fire/soda fire kilns were developed in ancient germanic nations. Both create very interesting natural surface textures that are dependent upon the position in the kiln a given piece is fired.
I am an expert of electric firings and automatic kiln programing, I studied under a professional sculptor for years who specialized in this area and since those days I've expounded apon that knowledge. Firing in a soda or wood kiln is more of a treat for me.
-Sol Zimmerdahl

Thanks Sol. It was a National Geographic article I think, where I saw how the wood kilns in Korea and Japan were set up in sort of a long tunnel on a hillside, and the pottery was fired progressively as the fire advanced up the hillside. It took days to set them up before firing, the apprentices being supervised by the master. Thousands of clay objects were fired during one session, with a minimum of fuel being used - very fascinating.

OK so I remember now about the salt or soda being "thrown into" the kiln to give the objects that special glaze. I took an art class in high school in which ceramics was part of the curriculum, and I used to make clay pipes from clay which I dug myself in a swampy area in Oregon City (just outside of Gladstone) and fired them in a section of chimney flue using charcoal briquettes. The clay was yellow and fired to a nice cherry red. I became kinda famous in my little circle of friends since I knew how to do that.

> Nick

Nick,
That does sound like a fun way to take advantage of the differentials in the kilns temperature and atmosphere based on placement, and with a natural clay to, that is exciting!
Wood firings are quite the process, I recall workshifts of chopping wood, followed by late nights of stoking and then back to more chopping! Some of the anagamas are very ingeniously designed, using heats desire to rise as a means of continuing a massive firing. Some I've heard can reach cone 14! I'm hoping to get involved in another wood firing soon.
-Sol

Yeah, there's a nice little write-up on Wiki :

Wikipedia > Anagama kiln

I remember from that Nat Geo article it was at the very top of the hill, where the heat was the most intense, that the best porcelain pieces were produced ☺

@GeologicalForms Sol! I love your planters!!!

Thanks Christie!
I did quite well at Clayfest. The Sempervivum are always the stars of the show in my handmade containers, it's really what got me so involved with this forum. Such easy going plants, once you've got a good soil mix going they really work well in even the most obscurely shaped pots.

Nick,
I love the sheen porcelain often gets in wood firings, here is one of mine...

This wood ash glaze drip is a nice touch as well...

I was using a much darker clay once in wood fire and got a metalic gold sheen that is really stunning...

I still have these pieces because I increase the price based on the excess labor required to fire in a wood kiln, unfortunately most bargain shoppers aren't aware of the difference, so they have just become "my" pieces and I am happy to keep them.
-Sol Z

Sol ~

I don't think I'd part with them either! The porcelain piece with ash glaze drip, and the way that it's planted, is truly a work of art ☺

> Nick

Much appreciated Nick
-Sol Z

You are so welcome Sol ☺

I used to do ceramics. perhaps I will go back again and try to some some planters. Won't be as nice as yours, but would be fun.

Christie,
You should! It's a lot of fun, and there's room for expeiramentation because these plants really alow for some interesting shapes to be successful. Hardy succulents are the best! Cynda from the nursery "Perennial Obsessions" also makes ceramic planters with sempervivum. Her work is fantastic, she uses glazes and textures well to embellish her work. Like my own, she tends to sculpt irregular shapes. Our work differs in that she uses more finished edges and surface patterning, where I try to keep my texture as random as possible and my surfaces are usually rough.
-Sol Z