As you walk up the ramp to the “The Secret Life of Earth,” the latest mega-exhibition at Baltimore’s American Visionary Art Museum, a constellation of colored objects hang overhead. At first, they look like a mobile above a baby’s crib or playful sculptures in the vein of Alexander Calder. But what you are looking at is waste: The ghosts of water bottles past. Last week’s trash, resurrected.

Gathered over 20 years, by artists Judith and Richard Lang for “TBD,” the work is a collection of debris that washed up on the shore of Kehoe Beach in California. In the museum, the objects become a picture of human profligacy, dangling over you — not unlike our pending environmental doom.

It’s no coincidence that, as our world gets more polluted, the minimalist aesthetic has become more popular. Our sleek smartphones, sterile chain stores and clean modern spaces tell lies of austerity. AVAM is uninterested in this illusion. The museum sometimes feels like an exercise in filling as much wall space as possible. And in “The Secret Life of Earth,” the tendency toward maximalism takes on added meaning. Here, the rich abundance of the natural world contrasts with the manufactured decadence of consumerist waste. As the exhibition argues for conservation of resources and curtailing the rampant consumption destroying the planet, it does so in the vernacular of excess.

There is a wall crammed with giant paper roses. An entryway with massive sticks made to look like a the nest of a bowerbird. Six extravagantly bejeweled primates by Johanna Burke look like they may have gotten lost on their way from the Rainforest Cafe to a Mardi Gras parade. Psychedelic paintings with trippy fractals might convince you your head is as full as your visual field. It’s a show that you have to take on its own terms. Here, more is more.

But love of the decorative should not be mistaken for lack of seriousness. Seemingly playful works have dark undertones. A gold-clad Pinocchio sculpture by Hubert Le Gall seems to have severed its own nose with a chain saw. It’s meant as a symbol of all the climate-change deniers, the wall text says. Beside it, a stuffed polar bear in Mars Tokyo’s “Teatro Dell’ Estinzione” — or “Theater of Extinction” — is just a cute plush toy, until you realize the figure has been made in the image of a bear emaciated by starvation. When the world ends, Tokyo seems to say, we will exit through the gift shop.

Throughout the show, bleak facts about climate change come in ample supply. Bulleted lists — 10 points about “everything meat lovers need to know”; seven points about the state of soil; 10 more about mushrooms (the fun ones and the deadly ones) — match the mood of maximalism.

The artist bios, too, go a bit overboard — some running a full page in length. They include unexpected details, such as where Burke was conceived or how psychedelic artist Alex Grey’s first LSD trip converted him from atheism to “radical transcendentalism.” You learn that the surrealist works of Christopher Moses are, at least in part, the result of an eye condition that causes him to see double. All inspiration, be it from drugs or Dali, is valid here.

AVAM shows what’s known as “outsider art,” which historically includes works created by people outside the mainstream for a variety of reasons: disability, homelessness, mental illness or lack of formal training, among others. It’s a fraught category but may be helpful in understanding the merits of the show.

Many of these artists prioritize connection to the Earth over traditional kinds of success. Often, they exist far from the systems and institutions that have allowed us to exploit the planet. Who better to express urgency about the climate emergency?

Part of the barrier to understanding our environmental crisis is visibility: the slow, imperceptible burn of the planet over decades and the way the consequences of climate change often — for the privileged — remain out of sight.

With the installation “What’s Cooking,” artist Bobby Adams frames climate change with the acute, everyday urgency of a pot boiling over. A kitchen scene shows penguin and monkey figurines frying on a stovetop, and the Earth glowing orange, burning in the oven.

Another installation, by Santiago Navila, gives life-size importance to the microscopic crisis of plastic bag fragments polluting the ocean. At first, the space feels meditative, cocoon-like, with videos of wild life projected on dozens of large fabric panels. But as the film progresses, it begins to talk about pollution. And as you watch, there’s a suggestion that the panels themselves are meant as parallels to the pollution, and the dark exhibition space becomes as claustrophobic as the garbage-infested sea.

While these wake-up calls to our own waste are certainly effective, many of the artists seem more interested in using excess as a way of expressing reverence for nature. You see this in Grey’s highly detailed, X-ray-like paintings of the human face — where the vivid veins beneath the surface echo the network of celestial bodies in the sky. You see it in the painstaking beading on Burke’s bejeweled primates, executed with religious attentiveness.

For every bit of man-made excess the exhibition condemns, it shows us a dozen times over that if we look close enough and deep enough, natural “excess” is everywhere. And better yet, celebrating it won’t cost us a planet.

The Secret Life of Earth

American Visionary Art Museum, 800 Key Hwy., Baltimore. 410-244-1900. avam.org.

Dates: Through Sept. 5.

Admission: $15.95; $13.95 for seniors; $9.95 for students, children over 7 and military personnel; free for members and children 6 and under. Timed-entry tickets required. Face masks required for all visitors over the age of 2. Please check the museum website for additional visitor guidelines.