Why southern-hemisphere grasses suit mild climates
Grasses and grass-like plants from Australia and New Zealand are widely used in mild, frost-light regions. Many are evergreen, many tolerate dry spells and some cope with coastal wind and salt. Their limitation is cold: several are only reliable in the warmer end of the hardiness range, so check your winter minimums first.
This article also covers San Diego and similar Mediterranean-type climates, where these plants are popular.
Australian grasses and grass-like plants
- Wallaby grass (Rytidosperma species): described by Gardening Australia as an all-rounder that copes with heat, dry and frost. It has a light, low profile, suits verges and soil stabilizing, and its silvery flowers turn wheat-colored as seed ripens. It also supports moths and butterflies.
- Common tussock grass (Poa labillardierei): a graceful, tough tussock to roughly 1 to 1.2 meters that moves in the breeze. It softens hard edges, works well planted en masse, and gives habitat to insects and small reptiles. Allow room for its natural dome shape.
- Tufted hedgehog grass (Echinopogon caespitosus): a small, slender grass with a soft, bristly seed head, suggested for pots among bright perennials.
- Matt rush or lomandra (Lomandra species): an evergreen, grass-like plant for sun or shade. It is described as drought and salt tolerant, with hardiness roughly zones 8 to 11. There are many cultivars, including compact ‘Tanika’ and ‘Lime Tuff’.
- Flax lily (Dianella): strappy foliage, small blue flowers and blue berries. It is tolerant of drought and salt, suited to warm zones, and available in compact forms.
Small New Zealand grasses
New Zealand nurseries recommend a number of smaller plants for borders, pots and low-care gardens:
- Orange tussock or New Zealand hair sedge (Carex testacea): orange-bronze foliage, good for mass planting, coastal areas and low-maintenance gardens.
- Dwarf toe toe (Chionochloa flavicans): lush green foliage with mini plume-like flowers.
- Lomandra ‘Lime Tuff’ and ‘Tanika’: reliable, neat and good looking through the year.
- Mondo grass (Ophiopogon japonicus): durable and compact, useful for texture and ground cover. See how it compares in liriope vs mondo grass.
- Libertia (New Zealand iris): golden leaves with white flowers in spring and summer.
- Blue fescue (Festuca glauca): not a New Zealand native, but widely sold there for fine, silvery-blue foliage. If it thins in the center, see why blue fescue dies in the center.
Ornamental grasses for San Diego and similar climates
San Diego’s mild, mostly dry climate suits drought-tolerant plants from Australia, New Zealand and California. A few options that work in this setting:
- Lomandra and flax lily (Dianella) for evergreen structure with low water use once established.
- Deer grass (Muhlenbergia rigens): a California native bunchgrass often used in water-wise plantings.
- Berkeley sedge (Carex divulsa) and California gray rush (Juncus patens): native, grass-like plants for texture and ground cover.
- Blue fescue and little bluestem: adaptable choices for sunny beds. See little bluestem varieties.
Caution: some widely sold grasses, such as purple fountain grass (Pennisetum setaceum) and Mexican feather grass, are considered invasive in parts of southern California. Check local invasive plant lists. For the wider plant picture, read the best outdoor plants for San Diego.
Planting and care
Advice from New Zealand growers is useful for grasses anywhere mild:
- Soak new plants in a bucket of water until the bubbles stop.
- Score the root ball. Make vertical cuts with a sharp knife to encourage new roots.
- Plant to pot depth. Planting too deeply can cause rot; too high and the plant dries out.
- Water regularly until established, especially in dry periods.
- Brown tips are normal. Foliage tips die back naturally and do not need removing.
- Do not cut hard. Tui Garden advises against cutting New Zealand grasses to the ground, since they can be very slow to recover (not every grass needs a hard cut; see should all ornamental grasses be cut back in spring?). Thin out old growth by hand or with a rake once a year in late winter or early spring.
- Feed lightly in early spring if needed.
For hole size, Gardening Australia suggests digging twice the width and depth of the pot, pre-soaking the pot, and watering in well after backfilling.
Are ornamental grasses invasive?
Some are, depending on region. Grasses that seed freely can escape into natural areas, and some warm-climate favorites are regulated or discouraged in places. Clump-forming, sterile or native choices are the safer default. Always check your local environmental or extension agency before planting seedy species.