Joan Mitchell’s new paintings suggested plants. All along, Mitchell’s work has often seemed to refer to Monet’s waterlilies—in its grouping of large canvases into three- and foursomes, in its complicated green and blue surfaces, in its control of individual sections of canvas by the deployment of the right planes and accents of color. This is more true than ever for the new work. Some of the titles refer to plants outright: Straw and Weeds. The profusion of greens—emerald; forest, bottle, grass—and the luxuriant variety of Mitchell’s brushstrokes contribute to the effect of leaves and stems, of something growing.

Mitchell offers a sort of post-Alexandrian, Hellenistic version of Abstract Expressionism, an anthology recapitulating all the great ’50s tactics: the strokes, the drips, the smeared areas of color, the dramatic juxtaposition of colors slashed across each other, the control of space with the fewest of marks. Mitchell is the technically brilliant pupil who supplants the fire of the original with careful, considered composition. One may question the originality of her techniques, but not her versatility or proficiency. She treats this kind of brushwork as idiom and turns it by new combinations into a rhetoric that builds strong pictures.

Mitchell’s strokes can be roughly categorized into two basic types—blades and petals, they might be called, after their botanical suggestions. A blade, a painted line with a little twist of energy, recalls de Kooning. The petal, a short, solid placement of paint, recalls Guston and others. In between these two paradigms there are samples varying across nearly the entire range.

Mitchell’s canvases seem to have thickened and become tighter since her large show at the Whitney a couple of years ago. Unfortunately, this concentration does not always work for the best. Mitchell’s brushwork can form layers and planes that subtly interact with one another, the way the different techniques and the different portions of the canvas also react with each other. But several of the canvases in the current show are simply too small to open up to Mitchell’s best effects. They seem to have been carved from the hearts of larger, failed paintings.

With no grand gestures at the center, no “fast” patterns to aid comprehension, no “hooks,” Mitchell’s are slow, studied paintings that demand long viewing. They are like complex jazz or rock instrumentals where patterns at the second and third levels are as interesting as those at the primary level, but emerge only upon long and repeated listenings. Mitchell’s strengths are those of the virtuoso: her work is improvisational but formally tough, lyric but extremely difficult.

—Phil Patton