Creative Foundations

Aesthetics

 Everyone has the capacity to assess beauty without any special training, whether that is in a face or a landscape or in architecture. Bonsai inevitably invoke a response in people with an appeal to both the heart and the mind. This confirms bonsai’s status as an art form, which is why when we place one in a container the choice must create a harmonious union. 

While there are all sorts of guidelines to pot selection which codify what has worked before, we can all trust our emotional responses to feel what works and what doesn’t.

In many ways the container frames the bonsai in the same way a picture frame frames a painting. There are conventions at play in that selection too. The parameters of that choice are analogous; the width of the frame or depth of the pot to colour compatibility to level of complexity or ornamentation to questions of comparative valuation with the work they contain.

Those choices are driven by aesthetic appeal and an intuitive judgement of the parameters of the design. We all know when that appeal is present but how can it be explained? The difficulty is that explanation is a cognitive or thinking process when aesthetics is all about emotional response. Classically aesthetics was a branch of philosophy dealing with the nature and an appreciation of beauty. An example of ancient aesthetics in Greece through poetry, is Plato's quote: "For the authors of those great poems which we admire, do not attain to excellence through the rules of any art; but they utter their beautiful melodies of verse in a state of inspiration, and, as it were, possessed by a spirit not their own." (Wikipedia)

The Japanese craft arts are possessed by a variety of ideas which are reflected in their wider society through the things which are important to them. This set of ideas informs their artistic aesthetic. Bonsai and ceramic arts share elements of this aesthetic. Those most influential in my pottery practice are the ideas of Wabi Sabi and Shibumi. Simple subtle unpretentious elegance which embraces the imperfections of the making process and which celebrates natural forces and natural colours in satin glazes is the aesthetic I pursue.

So the aesthetic appeal we are looking for in the union of container and tree is nothing less than an inspired admiration of nature and beauty, which is not composed from a set of rules, but appears inspired and possessed by a spirit not their own.

Artisanal attributes

In the days before commoditised mass markets, production line factories and global brands the things people needed were made by artisans; makers who practised handmade craftsmanship using manpowered tools to create aesthetically appealing functional items. Contemporary market dynamics only serve to amplify the differential and the value now placed on high quality artisanal products. Having one set of hands engaged in all the stages of the process of making imparts both identifiable physical character and the spirit or personality of the maker to the work. To understand this hold a crafted work, know where it came from and feel what has gone into its making.

Unfortunately a simple matter of economic efficiency has pushed artisans to the margin with their ongoing existence depending on the support of those who appreciate and are willing to pay a margin for the intangible attributes. Japan with its Living National Treasure status (actually, literally, ‘keepers of important intangible cultural properties’!) for master craftsmen has an acute appreciation of these traditions and their value.

My goal is to produce ‘artisanal’ quality bonsai pots, made with one set of hands and one spirit engaged in all stages of production, to a high standard of craftsmanship and aesthetics; making suitable partners for harmonious union with great bonsai trees. 

I should say that there is a good deal of mind engaged as well. The climb up the learning curve and proximity to success can only be advanced by exploring the underlying ceramic body and glaze material science. We are better artists for a deep understanding of the medium we work in and are fortunate to have so much knowledge readily available at our fingertips compared to the centuries of technical evolution of the early Chinese glaze development.

The stages of production and choices to be made are many.

Clay bodies

Clay selection is the first, which in turn channels subsequent choices. For bonsai pots both Earthenware (low to mid fired) and Stoneware (mid to high fired) are used. Terracotta is a low fired Earthenware clay. Porcelain is the third principal clay body classification. It is a high fired material not regularly used for bonsai pot manufacture.

Most people have a good understanding of the nature of fired earthenware or terracotta clay. It is much more porous than stoneware and also not as robust. In warmer climates this porosity offers both the pores and free moisture which is the perfect combination for the development of vegetative patina. Within a very short time a terra cotta pot will begin to be hidden from view making display problematic; and it’s not easy to get off. In colder climates which may be prone to frost, moist earthenware can fracture as the absorbed moisture expands as it freezes within the pot wall. Earthenware has a moisture absorption of between 10% to 15%. The cheapest pots you can buy will be mass produced unglazed earthenware pots typically dark brown heavy walled vessels that are useful only as temporary training pots. A mica pot or neatly made wooden box would be just as effective for this purpose.

Stoneware is fired to a higher temperature and vitrifies to a glass like compound with a moisture absorption of about  2%. At these levels it is effectively resistant to freezing damage and the surface of an unglazed stoneware pot will stay much cleaner than earthenware. You can generally tell stoneware pot by the clear bell resonance with a flick of the finger. A spot of moisture placed on the unglazed surface will also differentiate the clay body. The urban myth of the horticultural superiority of earthenware for its capacity to ‘breath’ has been thoroughly quashed by plastic pots in the nursery industry and modern horticultural practices. The beautiful thing about working in stoneware is as the name implies that the clay body is transformed into stone, which will then remain durable and unchanged for centuries. That is not to say that it is unbreakable as you will find if you drop one onto a hard surface!

The higher the firing temperature the more than proportionate demand for energy and so straight away there are cost implications, but the decision is an easy one; stoneware wins hands down. The transformation in the kiln is miraculous to observe. From bisque firing where the pot will have already contracted 5% in shedding all water, it will contract a further 7% or 8% in the final firing and the clay material transforms in a soft ‘plastic’ state to an extremely hard material back at room temperature.

 Finish - stains and glazes

Tradition dictates that conifers be placed in unglazed pots. With a concession to that tradition I think every other species looks better in a glazed pot. Putting a mature elm or maple or temperate evergreen or fruiting/flowering tree in a dark unglazed pot would be like framing a great painting in a plain flat brown frame. You could just do so much better than that. The one exception to this is that there are very few applications where a high gloss finish would be the optimal choice. It is also generally recognised that the surface of a darker unglazed pot which might reside outdoors will need some 'help' to get into a presentable state for exhibition. The surface can look like a piece of timber that's screaming for some oil. A little application of oil or wax and a buff will restore the surface to one with a hint of satin and glowing with health, just like you might get with a good satin glaze finish.

A glazed surface on the outside of the pot is the most durable surface to have in contact with the elements and offers the design flexibility to colour match the tree, reflect the value of the bonsai and enhance the overall composition. While we do not want the pot to be THE focus of attention, at the same time we should not allow the quality of the pot to reflect adversely on the quality of the bonsai. Better to find the middle path.

Most commercially available stoneware clays fire a white of buff colour though some are darker or have been darkened. This is probably because a lighter body offer more luminous glazes. Staining is an alternative means to introduce colour variety to the fired colour of an unglazed stoneware pot. A thin wash of oxide of iron or manganese for example applied to the bisque fired pot is an effective way to impart darker tones from buff through to dark red browns and brown browns when fired to maturity, if that is a preference.

Glazes are a molten glass like mix of natural minerals and oxides. The composition of the glaze is entirely at the discretion of the potter. Colour and surface finish (from gloss to matte) objectives are the usual drivers of glaze composition selection but just as important are the fit of the glaze, so that you do not get unintended surface cracking, as well as stability, which is having enough of the key ingredients. A crazed glaze for example, which is the result of poor fit will reduce the strength of the underlying ceramic by as much as 50%. Achieving objective colour, finish, stability and fit is sometimes a tall order. If you want to make a glaze for service exposed to the elements then the best long term performance will only come by staying within established stability limits. Understanding and applying the underlying glaze chemistry is a prerequisite for bonsai pottery glaze formulation. 

My glazing goals are to produce well fitted, stable high calcium satin to matte surface glazes in a variety of understated principally ‘pastel’ tones. These glazes will offer good tree/colour compatibility, ease of surface maintainability and resistance to surface damage and environmental attack. These features offer the best long term prospects, creating a pot that can enhance the bonsai union and be in service indefinitely.

On the economic front glazing requires a second firing and brings with it a whole new set of challenges in maintaining dimensional stability as the material transforms and contracts. This will make the glazed stoneware pot the more expensive.

Container shape and proportion

Finally a question of shape. Round pots, though most easily made on a wheel are only used with limited classes of bonsai. Oval and square pots can be made in moulds or fully hand built. Another way to make an oval pot is to turn up the wall section on a wheel and then arrange it on an oval base. This works best where the wall shape is close to vertical. 

Regardless of how the pot is initially shaped there are opportunities for secondary ‘alteration’ to the wall profile. I like to use press moulds following the Japanese model and then alter the form to a range of profiles and pot heights. This certainly limits the pot footprint to the number of moulds you have and so there is always an element of hand building from scratch, which applies in particular to commissions. In my early practice I have focused on pots over 350mm in length to fill a particular need. The rectangular form is probably the more taxing shape because of the challenges in containing the stresses and strains exerted during drying and firing to maintain dimensional stability and the larger the pot the greater the challenge.

So rectangular, glazed, stoneware pots will be the most expensive. You could say life is like a glazed stoneware pot; the most costly and difficult to make are usually the most desirable and the most expensive to buy.

The art in making a pot comes into play with the proportions, not only of length, width and height but also the incorporation of a rim, the wall profile, the radius of any curvature, the foot size and plane of attachment, the size and position of ribs or other decorative effects on the pot wall and many other minor design details, any one of which can add or detract from the overall visual appeal. It is almost impossible with hand-made pots to eliminate all pyro-plastic deformation through the many stages of production and what remains contributes to the character of the pot as a natural element of the artist’s crafted aesthetic. Imperfect symmetry is after all generally more natural and attractive than the absolute.