Budding sculpture

As any strong basic, simple design should, magnolias have lasted a very long time. Their early ancestors go back at least one hundred and fifteen million years and rubbed shoulders with dinosaurs and pterosaurs. They may well have looked on in amazement as the first birds known to earth began to flap around in the air just above ground level. Magnolias (to put it another way) are certainly Cretaceous and may even be positively Jurassic; among flowering plants they are as primitive and elemental as any.

There is something emblematic about the unfussed, boldly formed flowers (and leaves) typical of the magnolia. There are many variations on the theme, of course, but think of a magnolia and what first springs to mind is that rounded, slightly stiff, voluminous arrangement of petals.

These flowers are often likened to a goblet or a chalice, though logically the simile should be reversed: manmade containers and vessels owe their most graceful and globular formations, so comfortably held in the hands (the very gracefulness of vase and jar and amphora) to the primary example of such natural shapes as the magnolia.

Here is the essence of flower shaping, a fullness balanced by discretion, a vitality balanced by sturdiness. As Stanley Spencer's scrupulously realistic painting shows, a magnolia can flower extravagantly, can even carry a stunning array of bloom, but at the same time its particularity and structure predominate. Each shell-like bud, each upstanding flower, has firm intentions. This is not a plant in which the stages of bud, bloom and seed look inconsistent with each other. The flowers are even somehow similar in character to the leaves , and both relate with no-nonsense directness to the woodiness of the thick branches. Every part is adequate and looks tough.

Even in colour there is sensible restraint, as though dazzle and brilliance would in some way not be quite proper, and gaudiness out of the question. The kind of blossoming which smothers some trees in a massive swarm of flowers like a snowfall, a frothy sea of faces - that is not the magnolia's manner. This tree deals in largeness, in enough but not too much, each petal, each bloom, notably individual.

At a loss for words to describe the difference of magnolias, writers (though as far as I can ascertain very rarely poets) have strained themselves: the flowers are like ''light bulbs''; like ''pigeons settling''; their tone and surface are like thick mixtures of ''ivory'' and ''dense cream''; their texture smooth and soft like ''youthful human flesh''! Less fantastically, some have found it only possible to see them in terms of other flowering plants - of tulips, crocuses, lilies.

Though America is the home of many fine magnolia species, they possess an air of Orientalism.

They suggest long and quiet association with Chinese temples. They carry with them, wherever grown, something of the very ancient and hallowed, as if they deserved a symbolic respect on a par with the lotus. As one writer has observed, the Far East, China and Japan, are the headquarters of the magnolia family.

Japanese ink painters have paid tribute and decorated scrolls with magnolias: a single, branch extending across the page, for example, holds up a few perfectly placed buds like flames, and, perhaps, no more than a single opening flower, its petals edged with fragility. Artists find what they are looking for. The Englishman, Stanley Spencer, saw his magnolia quite differently - not as some selective trailing movement of brush and ink on white paper, but as a space-filling accumulation of important looking forms. His paint showed it to be not so much a thing of light and grace, as a steadily growing, living object.

He celebrated its apparent stillness rather than its surprising suddenness, its permanence, as if made of wax.

''It's as good as anything I have done,'' was his own assessment of this painting, made in 1938, a comment which goes against his habitual downgrading of the landscapes he painted as differentiated from the figure-scapes of his imagination. ''Magnolia'' may not richly engage the imagination, but it still has the patient virtues of Spencer's rather dogged style and his desire always to include, in an all-over composition like a tapestry, every last thing of interest, for everything in Spencer's art has identity, and he avoided an impossible cluttering by a clear grasp of forms, large and small: he didn't much like empty spaces in his pictures. His meticulous realism carried into the twentieth-century some of the literal delight in exactness of the Victorian pre-Raphaelites.

Here his prosaic English approach seems completely in tune with the magnolia, with the unfanciful beauties, the plain glories, of that almost sculptural flowering tree so favoured in English gardens.