Greenwave Casuarina

Greenwave Casuarina (Casuarina glauca 'Green Wave') is a prostrate native groundcover, not the upright she oak the name suggests. It stays around 60cm tall and spreads to 3m, laying down a soft weeping mat of fine green needles that moves in the wind. It is fast, tough and one of the very few plants that handles salt, wind, drought and waterlogging in the same position.

Why you'll love it

• It spreads, it does not climb. One plant covers up to 3m of ground at only 60cm high, so it never blocks a view or a fence line.
• Fine texture that keeps moving. The weeping needle foliage catches wind and light, giving a bed movement that flat leaved groundcovers cannot.
• Coastal proof. Salt spray, sandy soil and constant wind do not mark it, which is rare in a plant this soft looking.
• Wet or dry, it copes. Drought tolerant once established and equally happy in ground that stays damp after rain.

Where it works best

Groundcover and mass planting. Plant 1.5m apart for full coverage. At that spacing the mats meet in two seasons and the fine foliage smothers most weeds beneath.

Retaining walls and slopes. Plant along the top and let it spill over the face. The root system binds loose soil, which makes it a practical answer to an eroding batter.

Coastal gardens and poolside. It shrugs off salt and splash, and because the needles are fine rather than broad they cause less mess around paving than most shrubs.

Growing Greenwave Casuarina in Australia

Position and climate. Full sun for the densest mat. It grows across tropical, subtropical, warm temperate and cool temperate gardens, and it is frost hardy, so it suits most of the country apart from the harshest arid interior.

Soil. Almost anything. It takes sand, clay, saline soils and ground that holds water after heavy rain. No soil improvement is needed beyond loosening a compacted bed before planting.

Water and feed. Water weekly through the first summer to establish, then it looks after itself. Feeding is optional; casuarinas fix their own nitrogen, so a light native fertiliser in spring is more than enough.

Pruning. Trim the outer edges once a year in early spring to keep it inside its allotted space and to thicken the centre. It responds well to a light shear and does not need hard cutting.

What to expect when it arrives

It comes in four sizes: 140mm in packs of ten, 200mm in packs of six, 250mm in packs of three, and single 300mm plants. The 140mm and 200mm packs are the economical way to plant a bank or a large bed, since a fast grower like this closes the gap quickly. The 300mm gives a fuller plant from day one for a small area or a pot.

Young plants arrive as upright tufts and only start spreading sideways once they are settled, so do not judge the habit in the first month. Delivered Australia wide, with delivery from $29.95 and a minimum order of $300 before delivery, and every plant is covered by our 30 day healthy plant guarantee.

Plant care guides and related reading

• Read our guide to choosing ground cover plants.
• Browse the wider groundcover range.
• See other coastal and salt tolerant plants.
• Compare options for retaining walls and slopes.

Common questions

Will it grow into a screen?

No. This is a prostrate form that stays around 60cm tall no matter how long you leave it. If you want an upright she oak screen, choose a different casuarina.

How many plants per square metre?

At 1.5m spacing, roughly one plant for every two square metres. Stagger the rows on a slope so the mats overlap and no bare strips run downhill.

Can I walk on it?

Light foot traffic is tolerated, but it is not a lawn substitute. Use steppers through the planting if you need a regular route across it.