Moss lawn
They do not require mowing, fertilizing, or other amendments, and grow on almost any substrate (apart from metal), and at any soil pH and light level.
They can grow under conifers, swallowing the needles, but fallen broad deciduous leaves will kill them if not removed.
[3] Moss lawns can be used as a living mulch; they retain moisture, do not become compacted, and do not require annual replacement.
[2][4] A moss layer can act as a physical barrier to prevent germination of vascular plants.
[10] Traditional Japanese garden aesthetics avoids contrasts, symmetries and groupings that would create points which dominate visual attention, instead creating scenes in which visual salience is evenly distributed across the field of view.
The mottled texture and colour of moss (like that of rocks) can be used as part of such self-similar, evenly-distributed-salience designs.
[1][14] In traditional Japanese gardens, moss under deciduous trees is swept clear with a broom; more modernly, a leaf blower may be used.
[16] Overwatering can kill moss;[19] most species cannot stand being waterlogged, though some (like Sphagnum) require it, and others grow only underwater.
[15] Moss lawns can grow in anything from blazing sun to full shade, but different species are specialized to different light levels.
[2] Annual variations in sun exposure need to be taken into account; space under deciduous trees may be seasonally sunny, and require sun-tolerant species.
[10] Mosses do not grow roots into the soil, but most mosses need to attach rhizomes to the substrate in order to grow and remain in place; this is assisted by clearing and smoothing a lawn substrate and fairing a fillet between vertical and horizontal surfaces.
[9] While preparing for the moss, curves and mounds may be sculpted (this is easiest in clayey soil), and a hose may be used to erode the edges of shapes.
[9] There are moss species that grow on almost any substrate, including rocks, wood, or soil.
[28] To photosynthesize, moss needs sunlight (not necessarily direct), moisture, and temperatures above about -5 degrees Celsius (20 Fahrenheit) simultaneously.
Unlike most other plants, it cannot store energy for use later (except for in a storage protein used to repair cell walls).
[29] This means that watering moss will not increase growth unless it will stay wet, unfrozen, and at least slightly lit for some hours afterwards.
Spray times of 2–5 minutes, thrice daily, are typical,[10] but this may vary with the moss species.
[9][10] Transplanted moss may be secured to a new substrate with small twigs[10] or metal pegs.
Pond netting or tulle, held with landscape staples or tent pegs, or sometimes suspended on stakes, may be used to discourage wildlife from digging up moss.
[33] It is difficult to have moss thrive when transplanted even short distances; however, it is sometimes possible to set up a habitat for the desired species to colonize.
[39] Prostrate, creeping, branching; smooth sheetlike; fast to regenerate from fragments and faster-growing,[40] with maximum growth rates allowing them to double in size every six months.
[40] They can live constantly moist[29] or even submerged,[41] and may be watered as often as six times a day; however, if they become soggy they will grow fungi, including mould and mildew.
