Mondo Grass Ophiopogon japonicus

Green mondo is a tufted evergreen perennial rather than a true grass, spreading on short underground runners into a dense carpet of fine dark blades that arch over at the tip. Its quiet trademark is the flowering habit: small pale bells sit down inside the foliage rather than above it, which is the quickest way to separate mondo from liriope on a nursery bench. It is the standard mass planting for dry shade under established trees, along path edges, and in beds where a mower cannot go.

Ground conditions for a mondo carpet

Mondo is grown across most of the country, from cool temperate gardens through to the subtropics, and it holds its colour through winter in all of them. It is not fussy about soil type provided the ground drains, and it does well in the dry, root filled soil under mature trees where lawn gives up. Dig compost through the bed before planting, because a bed prepared once is a bed you never have to fix, and plant close together, since tight spacing is the only real lever you have on how fast the carpet closes. Water through the first two summers while the runners spread out.

The failure mode is weed invasion during establishment. Mondo takes seasons rather than weeks to knit together, and couch or kikuyu creeping in from a lawn edge will thread itself through the crowns while you wait. Pulling running grass out of established mondo by hand is slow, miserable work and it usually ends in lifting the lot. Kill the grass off before you plant, install a hard edge, and weed the gaps every few weeks until the foliage meets.

Green mondo against the other two mondos

Dwarf mondo is the same species held much lower and flatter, and it is the one for paver joints and stepping stone gaps. Standard green mondo makes a taller ankle high tuft with more presence, covers ground faster and is the sensible pick for whole beds. Black mondo is a different species entirely, near black in the leaf, slower again, and used in small deliberate drifts as contrast. If the ground you are covering is shaded and you are weighing up a broad leaf option instead, Xanadu fills the same brief at knee height in frost free gardens. Mondo is the frost hardy one of that pair, which settles it in most southern gardens.

Keeping a mondo planting even

Mondo needs no regular pruning. If a planting looks tired after several years, or winter has browned the tips, run a mower over it on the highest setting or shear it in early spring before new growth pushes, then rake the clippings off. Do that once when it is needed, not as an annual ritual. Feed in spring with a general fertiliser and again in autumn where the plants sit under hungry tree roots, and top the mulch up between clumps while gaps remain. Lift and split congested clumps in spring to fill bare patches rather than buying more plants.

Choosing a size

This plant is available in 8 sizes, from 70mm up to 10 Pack, priced from $16.95 to $229.00 per plant. The size shown is the pot the plant arrives in, which is the rootball, not the height of the plant. The smaller pots hold younger plants that cost less each and establish quickly, which suits hedges, screens and mass planting where the plant count adds up. The larger sizes carry several more years of growth on the farm and give height and presence straight away, which is what you want for a single feature position or a screen that cannot wait. Not sure which to choose? Read our guide to low water gardens.