Many Queensland seaside gardens are established on sandy soils low in essential plant nutrients but high in sodium chloride, or common salt.
The secret to achieving a good lawn cover in these exposed and sodium-rich soils is to find turf varieties that grow in salty soils. These are known as halophytic turf grasses. The following are the top four species for coastal conditions
Seashore paspalum (Paspalum vaginatum)
This turf grass will cope with occasional inundation by sea water.
It has a fine to medium leaf texture and produces a lush green cover. It tolerates relatively low fertility levels.
The three main varieties available in Queensland are Sea Isle 1, Sea Isle 2000 and Velvetene.
Buffalo grass (Stenotaphrum secundatum)
This grass is also called St Augustine grass in the United States.
Stenotaphrum secundatum can be confused with broadleaf carpetgrass (Axonopus compressus), which is commonly referred to as ‘buffalo grass’ in Far North Queensland.
S. secundatum is a similarly coarse-textured grass with a much higher tolerance of saline conditions compared to broadleaf carpetgrass, which can often be found in wet, shady spots in southern Queensland lawns.
The turf research group at the Department of Employment, Economic Development and Innovation (DEEDI) Redlands Research Station is evaluating buffalo grass selections for salinity tolerance. Buffalo grass is suitable for warmer parts of South East and Central Queensland. It is less suited to the coastal tropics as it thatches heavily.
Manila grass (Zoysia matrella)
Manila grass produces a tight, fine-textured and attractive lawn.
It is slow growing and only available from a few selected turf suppliers.
Green couch (Cynodon dactylon)
Green couch is a popular choice for gardeners along the coast, however it is known to be less tolerant of salinity than the above-listed species. It is also affected by low light levels during the extended tropical wet season.
The DEEDI turf research group has evaluated Australian green couch selections for their salinity tolerance. Of the overseas cultivars available in Australia, FLoraTeX has shown a higher degree of salt tolerance than other varieties in US trials. Hatfield and Oz-E-Green equalled the salinity tolerance of FLoraTeX in QPIF trials and Mountain Green (which is adapted for the tropics) also demonstrated a high level of salt tolerance.
|Species (listed in descending order of salt tolerance)||Common name||Sub-tropics||Wet tropics|
|Paspalum vaginatum||Seashore paspalum||Yes||Yes|
|Zoysia matrella||Manila grass||Yes||Yes|
|Stenotaphrum secundatum||Buffalo grass||Yes||No|
|Cynodon dactylon||Green couch||Yes||No|
Thatch: A layer of dead grass between the leafy green vegetation and the soil surface. Thatch should be removed periodically to maintain lawn health.