The Calming Art of Terrarium Building

NEW YORK — It should come as little surprise that the gig economy, that great upheaver of the service industry, has come for horticulture too. Still, it is sort of funny to hear someone say it out loud.

“Freelance mossing is a real job,” Michelle Inciarrano told me inside her plant studio, Twig, where she and her co-owner Katy Maslow hire many such mossers from Kentucky, Pennsylvania and Washington to supply good product.

The varieties they source are soft and springy and come in vibrant shades of green that cannot be found at most home improvement stores. High-quality moss, they say, can be the difference between a sad desk terrarium (we have all seen ‘em) and a lush, lively little world.

Twig occupies an unassuming space in the Ditmas Park neighborhood of Brooklyn, on a block with a restaurant supply store, an auto-body shop and a Russian bathhouse. Inside, the shelves are lined with assembled terrariums, potted plants and empty glass orbs waiting to become miniature ecosystems.

The décor is spare, save for a green wall constructed of plastic foliage; the floors are synthetic wood, the walls painted white. Inciarrano and Maslow run their weekend-only workshops at long tables in the center of the room.

No one really needs to be taught how to make a terrarium. Technically, all it requires is some rocks, dirt, moss and a container, preferably one made of glass. But the women behind Twig — avid crafters whose first business venture involved “subversive greeting cards” — elevate the hobby to a meditative art.

Each Twig workshop offers a brief crash course in the life of the humble moss. You will learn that these organisms come in more than 12,500 varieties, and that none of them have roots.

Unlike (most) humans, moss thrives atop its own decaying matter and is largely self-sustaining. It prefers a warm, humid environment, which a covered terrarium can maintain with a spritz of water every now and then. Plant care doesn’t get much more hands-off. But the assembly of a terrarium is an intimate exercise in plant cultivation and aesthetics.

On a recent Sunday afternoon, tables at Twig were set with brown paper bags and bowls containing our tools: glass jars with loose lids, giant tweezers, polished river rocks, peat moss soil, sphagnum, sand and crushed sea glass. It turns out that moss demands an entrance all its own.

We prepared our jars, filling them about one-fifth of the way with rocks, then packed a handful of hay into a dense layer atop them. Over that we sprinkled a cupful of potting soil. Then it was time for three types of moss (mood, sheet and palm) to be carried out of the fridge as if on a palanquin — and for the real landscaping to begin.

In her memoir “Life in the Garden,” Penelope Lively distinguishes the “real garden writer” from the “garden commentator.” The writer, she said, is unafraid of dirtying her hands in service of beauty. I grabbed a fistful of moss and ran my fingers over its furry surface, felt the cool of its soil in the center of my palm. Making a terrarium is not as involved as, say, mulching a rose bush, but it satisfies the gardener’s urge to cultivate.

Inciarrano demonstrated one of her favorite styles, manipulating her moss into a mountainous structure with a small beach (comprising sand and sea glass and a small animal figurine) at its base.

Many of us in the class followed her lead (creativity can be scary in novel media), though some went their own way, sculpting steep valleys filled with shallow rivers, or flat oceanside scenes. It felt good to exert some control over the environment, to shape it into something that looked habitable.

Tactile activities have found a place in the broad category we now call self-care: behaviors, classes and treatments that reduce anxiety and depression, and are meant to serve as counterprogramming to the endless cycle of devastating information in the world.

For an hour on a weekend afternoon, I did not think of anything except the microcosmic forest in front of me and whether its climate would suit a tiny rubber giraffe.

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