Ree Morton’s first large-scale US museum exhibition since 1980, “The Plant That Heals May Also Poison,” at the Philadelphia Institute of Contemporary Art, captures the unparalleled, heartbreaking hot streak, from 1971 to 1977, that constitutes her brief career. She got a late start: She was married with three kids by age twenty-five, and her subsequent pursuit of an art education was as arduous as it was anomalous. And then she died tragically, in a car accident, when she was just forty. So all of her work is early work, and in this show curated by Kate Kraczon, we see her in flux, forging her secret code, each major installation representing an astonishing leap forward on her sui generis path.

Wood Drawings, 1971, the earliest work on view, looks a little like one of those rock-climbing walls punctuated with footholds. Sixteen small units made of cast-off wood, marked in various ways with pen or pencil or little nails, adhere to the wall to make a quiet statement about what drawing can be. Morton quickly mastered, or intuitively knew, how to give her work a compelling in-betweenness. Her objects walk the line between painting and sculpture; her installations, as Lucy Lippard wrote, with puzzled wonder, in 1973, are something “between welcoming ‘environment’ and closed pictorial space.”

Morton’s cryptic, poetic, inexplicably endearing installation Sister Perpetua’s Lie, 1973, takes inspiration from Raymond Roussel’s proto-surrealist novel Impressions of Africa (1910), a work composed according to baffling rules only revealed after the writer’s death. Mounted like a plaque at Sister Perpetua’s start, a handwritten poster surrounded by diagrammatic drawings reads, “To the question, ‘Is this where the fugitives are hiding?’ the nun, posted before her convent, persistently replied ‘No’ . . .” Strips of black-painted wood form a precise outline, both cordoning off the space in which the abstracted-to-nonsense story unfolds and leading the eye through the narrative. The thin path winds its way along the floor to a simplified guillotine form with a dull wooden blade before ending at a fenced area that contains a painted tree stump. This cage or playpen is presided over by a big gray painting, like a chalkboard, emblazoned with a rune-like white oval.

Morton’s eccentric post-Minimalism is not only concerned with the formal questions of the day; her bare-bones precision and humble materials instead serve a something-out-of-nothing kind of sorcery and hint at the existence of hidden superstitions or associative Roussel-like rules. The strange, unpeopled vignettes suggest stripped-down carnival games, ritual sites, treasure maps, and traps. “In one respect Morton’s work seemed like an elaborate joke about materials and process art,” the also brilliant and under-known artist Rosemary Mayer wrote, again in 1973. “At first sight, because of her choice of materials, it seems like she’s doing one of those very serious ‘this is how it works’ pieces. Then you see how impractical and nonfunctional the parts are.” Morton’s peers captured the foxily critical attitude at play in her art, plus a magic something-else that remains as ineffable and fresh as ever.

Early on, Morton favored an aloof style of abstraction in her works on paper, producing drawings that evoke scientific sketches wiped of identifying detail, but in 1974, she proudly embraced the ladylike diversion of botanical illustration. The nonchalantly exquisite series “Weeds of the Northeast” features wood-grain screen-printed “frames,” lines of glitter, and faithfully rendered leaves. More dramatically, Morton’s discovery of the remarkable substance Celastic—moldable, plastic-impregnated fabric—dovetailed with her development of an exuberant conceptual sentimentality. After the muted palette and natural mate-rials of her previous work, there’s a Dorothy-entering-Oz moment as you cross into the world of her brightly painted, brittle Celastic drapery, bows, and flowers. The gallery is a trove of curiously festive handmade elements, breath-takingly out of place on the white walls. Her expansive installation Signs of Love, 1976, is a culmination of this decorative trend, a scattering of wonderful prop-like and ornamental things, including big watercolor portraits of fairy-tale royalty, giant rosettes, and wrapped ladder forms. Painted on the wall are a handful of block-letter words—such as MOMENTS, SETTINGS, and ATMOSPHERES.

Morton had unabashedly, without hesitation, changed course—at least it seems so—to participate explicitly in the feminist ennobling of gendered hobbies, craft, and the domestic sphere. Her work refers, with a unique balance of satire and fondness, to the suburban-mom turf of birth-day parties, embroidered samplers, scrapbooking, and Christmas. And while her objects from this era continue to hover between painting and sculpture, they also variously or simultaneously feel like signage, decoration, and fixtures. Some even light up.

The show’s intoxicating title work, which is installed at the start, beckoning visitors to enter this momentous exhibition, is an arched swag of Celastic, glossy with peach enamel and ablaze with five white bulbs. Beneath the embossed aphorism THE PLANT THAT HEALS MAY ALSO POISON colored “ribbons” hang, like awards, each labeled with the name of a plant. The hybrid sculpture/sign/sconce is mounted on wallpaper, its pattern of lions, tigers, and giraffes suggesting a child’s bedroom. Though nothing in Morton’s work particularly encourages us to interpret her words (rather than to simply register their presence and emotional drift), in this case the metaphor is too apt to resist. There can be too much of a good thing—of sweet-ness, irony, allusion—but Morton administers perfectly calibrated doses of each potential poison.

Johanna Fateman is a writer, a musician and co-owner of Seagull Salon in New York.