Long before moss became a houseplant in a jar, it was a florist's staple: the quiet green material that lines a basket, hides the mechanics of an arrangement and forms the body of a wreath. Step into almost any flower shop and there is moss somewhere, usually under another name and often doing the work nobody is meant to notice.
The florist's mosses, and their muddled names
Trade names for moss are gloriously unreliable. "Flat moss" or "sheet moss" is generally a genuine moss, frequently a Hypnum, sold in peeled-up sheets for covering surfaces. "Mood moss" tends to mean the rounded cushions of Leucobryum or Dicranum, wanted for their domed shape. Past those, the labels start to deceive. Reindeer moss is a lichen, the springy Cladonia dyed and preserved; Spanish moss is no moss at all but an air plant, a cousin of the pineapple; and the "Irish moss" of a garden centre may turn out to be a small flowering ground-cover. Sphagnum, the bog moss, keeps its own name and a set of uses all its own. Knowing what actually sits in the bag is worth the trouble, since care and conscience differ wildly between a plant, a lichen and a bromeliad; the wider muddle of mistaken identity is unpicked in moss, lichen, liverwort or algae.
Fresh, dried or preserved
Floristry draws on moss in three states. Fresh moss is living and soft, lifted not long ago and still green, used where it will be on show for a short spell and can be kept damp. Air-dried moss has merely been left to harden; it pales and turns crisp, useful as hidden packing where looks do not signify. Preserved moss has been steeped in glycerine and commonly dyed, which holds it pliable and vividly green for years with neither water nor light. Which to reach for follows from the job: fresh moss where it will be seen and watered, dried moss for bulk out of sight, preserved moss for anything that has to stay green on its own. That same preserved material filling a florist's order also makes the indoor panels covered in preserved moss walls.
The wreath, mossed from the frame out
A classic wreath begins with moss. The maker binds a wire ring tightly with handfuls of damp sphagnum or carpet moss, winding round and round with reel wire until it forms a firm, even green doughnut. That mossed base does double duty: it gives a surface to pin foliage and flowers into, and, kept damp, it works as a reservoir that holds cut stems alive far longer than bare wire could. Funeral and Christmas wreaths are still built this way, and the technique, called mossing, ranks among the oldest in the florist's craft. A well-mossed frame is what separates a wreath that lasts a few days from one that lasts a month.
The hidden mechanic of an arrangement
Most of the moss in floristry is never meant to catch the eye. A pad of it laid over wet floral foam disguises the green brick and slows it drying out. Sheet moss lines the open sides of a wire basket or a hanging container so compost stays put and the rim reads soft rather than mechanical. Tucked round the base of a planted bowl it covers bare earth and lends an instant air of something woodland and settled. The same trick of binding a rootball in moss and twine, carried further, becomes the Japanese craft of kokedama.
Sourcing it with a clear conscience
Where the moss has come from deserves a thought, because much of it is gathered wild and not all that gathering is gentle. Commercial sheet moss is often stripped in quantity from forest floors, while the sphagnum behind so many wreaths is bound up with the draining of peat bogs, ground that takes thousands of years to build and locks away great quantities of carbon. Choosing preserved or cultivated moss eases the pressure, as does keeping a mossed wreath frame from one season to the next instead of starting fresh each winter. Anyone gathering their own should do so sparingly and from where moss grows in plenty, by the field manners set out in collecting moss responsibly.
Keeping it green
Fresh moss in an arrangement stays green only while it stays damp and clear of fierce light. A wreath hung outdoors in cool, humid weather can hold its colour for weeks; the same wreath above a warm radiator browns within days. An occasional light misting revives it much as it does a moss garden, and a wreath base will take a whole soak in the sink to recharge. When at last it fades, fresh moss composts away cleanly, among the gentler ends any floral material can come to.