After a rain, look by the flowerpot and you will often find this tiny clump: green of the palest kind, each fine stem topped with a tilted little gourd. Squint close to see it; a passing breeze sets it swaying.

The Tiny Clump by the Flowerpot

After a rain, look by the flowerpot and you will often find this tiny clump: green of the palest kind, fine stems standing one by one, each topped with a tilted little gourd. Squint close to see it; a passing breeze sets it swaying.

It is so small it barely registers as present. But it is the best place to begin learning moss: no mountain trip, no wetland—just one rain, and the windowsill is enough.

— Botany Notes, self-inscription —

A fine stem tops a tilted little gourd,

and after the rain it is the first to claim the ruins.

What Is Inside the Gourd

That little gourd is its spore capsule, and inside are the spores. In youth the capsule wears a thin little cap; when mature it turns pear-shaped and hangs tilted, like a small monk shading himself under a straw hat.

Mosses do not flower and do not set seed; they reproduce by spores, and their life cycle includes a free-living gametophyte generation. Cord moss does the alternation of generations more plainly than any other plant—study one clump and you have read an introductory lesson in plant evolution.

The First to Come Back

Cord moss is a classic pioneer plant: on fire-scarred ground, freshly turned wall bases, and bare pot soil, it is usually the first to settle. It is not fussy about fertility; a little moisture is enough.

Once it has settled in, the mat holds a thin layer of humus, and only then do other grasses and seedlings find a foothold. On barren ground the first to come back and mark the spot is something this small.

• How to know it: Small moss; stems erect and slender; leaves ovate-lanceolate with a distinct midrib; spore capsules pear-shaped and pendulous, shaped like gourds.
• Season: Grows fastest after rains; capsules mature in the wet season; in dry weather the whole clump draws together and darkens.
• Caution: Loves shade and moisture, dislikes direct sun and dry wind; observe the capsules with a magnifier rather than poking them repeatedly.
• Relatives, not the same family: “Tai” and “xian” are often mentioned together, but they belong to different groups; cord moss is a true moss, while liverwort belongs to the liverwort class.

In Terrariums and Moss Balls

It is also one of the mosses commonly used in terrariums and kokedama: gather a small clump and ball it up—green when wet, faintly gray when dry—set it in a little clay pot, and you have a desk scene.

Two rules for keeping it: shade and moisture. Direct sun yellows it quickly; dry air makes it shrink. Kept in a glass container with frequent misting, it grows more steadily than it ever did in the wild.

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Keywords: cord moss · spore capsule · pioneer plant · moss