ORNAMENTAL GRASSES

True Grasses belong to the family Poaceae (syn. Gramineae)

Landscapers however often refer to grasses as any plants that have the appearance of grass: having long leaves and a clump forming growth habit.

In this broader sense, a grass garden can include plants that are not true grasses.

By adopting this broader definition, you are able to utilize a greater variety of plant affects to greater a “grass” garden.

Grasses and grass like plants create a very different visual affect to the type of garden we are so often used to seeing. A garden that is dominated by fine long leaves can create a “gentler” and more “relaxed” mood.

The affect of long arched leaves blowing in the wind can be even mesmerizing.

The Japanese identified this characteristic in grasses a very long timer ago; and have used bamboos widely in their gardens to create a mood of serenity.

Ornamental Grasses For Year Round Effect

Grasses provide a different effect at different times of the year.

With seasonal changes, grass foliage changes, and at times, flower heads emerge.

Flower heads may not be as brightly coloured as some plants; but they are graceful and can add a soothing element to any garden.

The fine texture of most grasses is a great contrast to most other plants commonly found in the garden.

Some grasses actually change colour in different weather conditions.

Changes in light conditions can also affect the appearance of grasses. Longer shadows in winter will make a grass garden appear different to how it looks in the brighter summer light.

Grasses are Diverse

Grasses are one of the largest families of flowering plants.  They range in size from tiny creeping or clumping species through to magnificent tropical bamboos.  There are many other different features:

·         Various foliage colours…red, blue, green and even gold tones

·         Thick and thin leaves

·         Upright and drooping foliage

·         Tall and low flower spikes

·         Different coloured flowers

·         Some are invasive; some are not

·         Some grow in very wet soil; some in dry


Ways to use Grasses In a Garden

Grasses can be used for much more than just lawn:

·         Plant a whole garden or section of a garden with nothing but grasses

·         In pots/tubs as a specimen

·         As a border or hedge to contrast with plants behind

·         In the gaps between paving stones

·         In narrow garden beds

·         With broad-leaved plants as part of a mixed garden bed

·         To attract seed eating birds



An Introduction to Some of the Ornamental Grass Like plants you may grow:

Arthropodium

Arthropodium strictum– A reed like clump with chocolate scented mauve flowers in spring.  Can die down in summer

Bamboo

Bamboos are a diverse group of grasses.  They range from small types suitable for a pot through to towering giants.  Some have invasive roots, others form clumps.  The timber from bamboo is used for buildings, tools, and even the reeds used by saxophone players!

Bamboo requires rich, fertile soil and an annual addition of manure and compost. 

They can be propagated by division of the roots or from stem cuttings. 

A particularly stunning bamboo with– spectacular black stems is Phylostachys nigra

Carex

Several named varieties of these reed like plants are available.

Likes moist or wet position.

Carex appressa– tall, tussock forming with yellow brown spikes in spring and summer

Carex fascicularis– drooping spikes and bright green leaves

Cortaderia  (Pampas Grass)

A true grass: named varieties are available.

Dramatic specimen plants.

Plant in clumps of three or five.

Propagation by division.

Cortaderia selloana  -is an environmental weed in some areas; but a treasured ornamental in others.

Dianella (Flax Lily)
Has blue flowers in spring and early summer.

Dianella revoluta– colony forming clumping plant

Dianella tasmanica - large clumping plant


Festuca

A true grass, this genus includes blue coloured ornamental grasses.

Most are low-growing, tussock forming grasses

Most prefer a hot, sunny position, some survive in the shade.

Border plants, perennial bedding plants.

Kangaroo Grass

A true grass, tough, low-maintenance plant that thrives in a variety of soils throughout <st1:country-region>Australia</st1:country-region>.

Themeda triandra– clumping grass with attractive seed heads in late spring/early summer.

Lomandra

Known as mat rushes; these are suitable for dry sites.

Lomandra filiformis­ – clumping plant with greyish leaves and yellow flower spikes

Lomandra longifolia – spikes of yellow flowers in Spring and early summer

Micolaena      (Weeping grass)

Is suitable as lawn alternative in shaded sites.

Microlaena stipoides– spreading grass with soft texture and tall green flower spikes


Pennisetum  (Fox tail grass)

True grasses that grow best in full sun.

These are considered a weed in some localities (eg. parts of Queensland), but are a widely planted ornamental in many temperate climates.

Poas

These are true grasses.

Group of hardy, large clumping native grasses .

Prefer well-drained sites and full sun.

Propagated from seed.

Poa bulbosa

Poa australis– fine blue/green foliage

Poa labillardieri– forms large clumps of fine pale foliage

Poa sieberiana

Restio             (Cord Rushes)

Prefer wet sites.

Restio tetraphyllus­– large clumping rush with attractive red/brown flower tassels in spring and summer. A dwarf form suitable for small water gardens is also available. 

Wallaby Grasses

Group of perennial native grasses.

Prefer well-drained dry sites.

Propagated from seed.

Choinochloa pallida– wiry clumping grass with reddish flower spikes

Danthonia racemosa– tussock grass with cream/green seed heads

Xanthorrea sp.          (Grass trees or Blackboys)

Not a true grass: they prefer dry sites and well-drained soil.

Xanthorrea australis– spectacular small tree with black trunk and grass-like foliage

Xanthorrea minor– small grass tree without a trunk, suitable for small gardens and pots

NB.  Grass trees are often taken illegally from bushland areas.  Only buy grass trees from a reputable nursery. 

BAMBOOS

Bamboos have had a long landscape association in tropical and warm climates. They have been used for construction materials for centuries.

Stands of bamboos can provide an Asian feel of theme to the garden, whether small or large varieties are used.

Clumping types produce tight stands of bamboos, relatively easy to maintain and good to use for most landscape jobs.

Running types have been known to escape into other properties and can be very difficult if not almost impossible to contain.

For most landscape jobs, clumping forms are the preferred bamboos to use.

Landscape use of Bamboos

Classic Chinese design places running bamboos at a distance to provide a vivid background due to its fine texture. Clumping bamboos were placed predominantly in the foreground, with a few placed between fore and background to harmonise the arrangement.

Clumped bamboos are best scattered sparsely over a landscape, not evenly positioned.

The number of culms left to grow and develop in the clump may affect the density of the clumps appearance. If too thick, it may cut out attractive views. If too thin, it may allow too much breeze through. A balance needs to be established, which will be different for each landscape location.

Thinning may also lighten the landscape by allowing light to permeate to the ground.

Running bamboos can be used to make hedges whereas clumping groups are best used as a standard tree specimen.

Paths which pass through a bamboo grove were called 'Bamboo Paths' according to ancient Chinese landscape architects. They are perfect cool zones to escape hot summers.

A classic location near pond or river banks, or near rocks tend to emphasis the structure of the bamboo and the surrounding features.

In domestic gardens serious consideration should be given to pest potential of the bamboo. If running types are desired, ensure planting location is far enough away from services and structures and that there is some kind of solid structure in the ground to control stolons. Bamboo has been known to come up through slabs of concrete. Placing running bamboos in pots raised above the ground can aid control.


Botanical Name

Common name

Bamboo Group/Type

Height

Culm Features

Leaf Features

Arundinaria anceps

-

Running

up to 4m

shiny green to matt green-brown

narrow and short

Bambusa eutuldoides

Dai Ngan

Clumping

12m

erect, dense

Bambusa glaucescens

-

Clumping

8m

matt yellow

Medium green

Bambusa heterostachya 'Variegata'

Variegated Malay Dwarf

Clumping

3m

Silver stripped

Bambusa 'Alphonse Karr'

Yellow Stem Hedge

Clumping

8m

Green with yellow stripes

Bambusa 'Golden Goddess'

Golden Goddess

Clumping

4m

Golden colour when mature

Medium green

Bambusa 'Riviereorum'

Chinese Goddess

Clumping

3-4m

Yellow

Fern-like

Bambusa oldhamii

Oldham's Sweetshoot

Clumping

10m

Straight

Dark green broad

Bambusa textilis var gracilis

Slenders Weavers

Clumping

5m

Thin-walled, slender

Small

Bambusa vulgaris 'Vittata'

Painted

Clumping

15m

Yellow with green stripes

Dark green

Dendrocalamus latiflorus

Sweet

Clumping

24m

Straight green

Large dark green

Drepanostachym hookerianum

-

Clumping

6m

Stripes of yellow, pink, pale green and cream

Green to 30cm long

Gigantochloa sp

Timorgiant Black

Clumping

20m

Mature to dark purple

Gigantochloa apus

String

Clumping

20m

Dark grey-green

Huge green

Gigantochloa atter

-

Clumping

20m

Straight green

Indocalamus tesselatus

-

Clumping

1m

Arching stems

Big shiny matt dark green

Otatea acuminata var azetecorum

Mexican Weeping

Clumping

15m

Slender black

Long narrow attractive

Phyllostachys aureosulcata

-

Running

10m

Mature to yellow

Small green

Phyllostachys humilis

-

Running

5m

Grey-green

Phyllostachys nigra

Running

5m

Mature to shiny black and arched

small

Pleioblastus fortunei

Running

40cm

Green

white and green striped

Pseudosasa japonica

Running

3.5m

Green

Shiny, leathery

Sasa veitchii

Running

1.5m

Dark green to light green

Dark wide green

Schizostachyum brachycladum

-

Clumping

13m

Erect yellow with green stripes

Schizostachyum

jaculans

-

Clumping

8m

Tight culms

Abundance of green

Semiarundinaria fastuosa

Column

Running

7m

Erect, green to dark brown

Thalmocalamus tesselatus

-

Clumping

2-4m

Erect, almost reddish in full sun

Blue-green

Thrystachys siamensis

Monastry

Clumping

13m

Delicate erect

Attractive fine


GARDEN DESIGN COURSES

Learn more about different garden types by taking a garden design course with Australian Correspondence Schools. With over 130 horticultural courses to choose from, you are sure to find something of interest. For further information or a free course handbook https://www.acs.edu.au/Courses/Landscaping-courses.aspx