Heroic artist a bad painter

A visitor clad in Frida Kahlo imagery looks at The Two Fridas, at the Tate Modern. Picture / Reuters

Frida Kahlo is a bad artist. She's a famous and popular artist, and that isn't hard to understand. There are many people who prefer pictures to be storybook illustrations - and if the story in question is the artist's own life, and if the life is a passionate struggle, and if the artist is a woman, and Mexican, and strikingly beautiful, well, so much the better.

If that's what you want from pictures, and you're going to be in London over the next few months, make haste to Tate Modern before the crowds become overwhelming.

If you wish to preserve your delusion that Kahlo (1907-54) is "one of the most significant artists of the 20th century" (as it says on the back of the Tate catalogue), then the one thing you mustn't do is look at her pictures face to face.

You already know what you like about it. You like the psychodrama allegories, the blend of Mexican, Catholic, Freudian and Marxist imagery, the iconic eyeballing self-portraits with the joined-up eyebrows, and the whole complex theatre of the self that these images play out, their postures of victimisation and heroism, dependence and resistance, torment and masquerade.

Before this exhibition opened, I hadn't seen more than one or two Kahlo paintings. I knew her work from picture books. It always looked like it had some force. But reproduction lies. It reduces, and flattens, and makes you forget what a picture is made of. In reproduction it hardly occurs to you that these images are paintings. In front of them, you're uncomfortably aware of it.

Kahlo can't do painting. She has no interest in paint or brush or canvas. She has no interest in the relationship between the paint and the thing that's being painted. The paint is a means only, and means nothing. Some of the portraits (not self-portraits) in the show's first room have a naive elan, a nice, bold, deadpan, "Sunday painter" flatness.

But later the handiwork becomes painfully weak and cautious. It comes alive only when Kahlo is putting down red paint that means blood - as in The Two Fridas, where the spilt blood pools and seeps and dribbles down the folds of the white skirt. That's a good bit.

But the show also has some of the worst paintings ever hung in Tate Modern. I think a responsible curator would have suppressed Kahlo's still lifes. They are helplessly, laughably incompetent.

Okay, fair enough, point taken, you may be feeling - but nobody ever claimed that Kahlo was a painter, least of all a painter from life. What she was, was a great image-coiner.

Oh, really? Let's think about image-making. The 20th century has some fine examples - work where the painting is nothing much but there's a knockout combination of subject and shape and stagecraft.

Think of Magritte's Attempting the Impossible, the man painting the woman's body on thin air, or Hopper's Office at Night, or Rego's The Policeman's Daughter, the girl with her arm down the long leather boot. All are strong, clear poster-pieces. Is there any image by Kahlo as memorable, as forceful?

I think there is one. Mostly, the way Kahlo puts an image together is shambolic and uncertain. The elements pile up with no feeling for shape, economy of content, emphasis, drama of colour. (Kahlo is, for all practical purposes, colour-blind.)

But there is one picture that hits. It's in the Museum of Modern Art, New York, and it's included in the Tate catalogue, but for some reason it's not in the show. Self-Portrait with Cropped Hair shows the artist, in a man's suit, sitting in a chair in the middle of an empty floor, with her dark hair cut mannishly short, scissors in her hand, and all her severed tresses strewn in clumps on the floor around her, or dangling lifeless over the chair.

It looks like a piece of performance art, not just in the subject matter - the public self-martyrdom - but in the way the scene makes a strong and simple sculptural tableau.

It's interested in the patterns of the scattered hair on the floor surface, in how the hair curls and droops around the framework of the wooden chair. Ignoring the useless painting of the figure, it is a memorable image. Almost alone among Kahlo's works, its attention is not just on the ideas it's trying to illustrate, but on the things it's depicting.

That is the central failure. Allegory comes alive only when its component objects have some life of their own. Kahlo stuffs her work with meaningful things and has no interest in them as things. It's a baffling failure. In that last picture, how could Kahlo not have been interested in the shape and sharpness of the scissors?

And in those self-portraits where her head and shoulders are framed by burgeoning leaves, or embraced by cheeky monkeys, how could she have taken so little delight, have put so little energy, into those leaves and monkeys?

The gallery of symbolic self-portraits is the core of her work. But through them all, she never shows any interest in her own face and body. I realise her body was in a bad way, from polio and spinal injury. I realise it's meant to have a painful stiffness - though with Kahlo's limited skills, every body she paints is as stiff as every other.

But the continually repeated face, always turned in three-quarter view with the eyes turned back to the viewer, always with the same pout ... I don't know if that was the face she invariably fell into when she looked in the mirror, or if this was just her formula "me".

Either way, the effect is like someone who writes out their own signature over and over. You might call that person self-transfixed. You'd never call them a self-explorer.

Kahlo's art is so bound up with her psycho-biography that I feel I ought to say something psycho-biographical about how she turned out to be such a bad artist. But there's no call for that sort of explanation. Why should she have been any good? The only point to be grasped is that - whatever may be true of her in person - her pictures are utterly lifeless and passionless.

A telling comparison would be with Stanley Spencer. He's another non-painting painter, another prominent egotist, but an artist of enormous passion. His burning egotism fills everything connected to him, even the smallest things, with life. But in Kahlo-world everything is inert. Whether this is a technical problem or a psychological one is no matter.

Of course, we know very well why people want Kahlo to be "one of the most significant artists of the 20th century". We know why her pictures have become "some of the most iconic images of the last hundred years". She fits so many bills so perfectly: woman hero; short life of pain; lots of affairs; married to a fat male artist, and held her own; personal and political; the self; cultural hybridity; on the left (but don't say Stalin too loudly). She has everything, indeed, that we might wish for nowadays in a modern artist. Except, utterly, the one thing needful.

- INDEPENDENT

* Frida Kahlo, Tate Modern, London, to October 9