Cottesloe at the bottom for using fertiliser near the beach

Using fertiliser on lawns near the beach lowered Cottesloe’s score. Picture: Will Russell
Using fertiliser on lawns near the beach lowered Cottesloe’s score. Picture: Will Russell
Using fertiliser on lawns near the beach lowered Cottesloe’s score. Picture: Will Russell Using fertiliser on lawns near the beach lowered Cottesloe’s score. Picture: Will Russell

COTTESLOE Council will change how it uses fertilisers after it was last among neighbouring councils in the 17th annual survey of the nutrient’s use by the South East Regional Centre for Urban Landcare.

“Specifically, Cottesloe is using fertiliser on foreshore areas which could wash into the sea,” centre chief executive Amy Krupa said.

The centre protects rivers and coastal waters from algal blooms caused by excessive nutrients, of which fertiliser comprises 80 per cent entering the Swan-Canning river system.

Mid-last year the centre asked councils how they spread fertilisers on public land, educated ratepayers about their use, monitored water quality and controlled developments to lessen the pollutant entering water.

Using 2002 to 2018 surveys, Cottesloe’s 37 per cent score was the lowest, while Subiaco had 57 per cent, Claremont 47 per cent and Nedlands 43 per cent, after the 72 per cent lead by both Bayswater and Vincent councils.

Ms Krupa said Cottesloe’s score was from not educating ratepayers about fertiliser use in gardens, not doing water monitoring and not testing turf to see if it needed the nutrient.

However, she acknowledged Cottesloe did not drain into the rivers system and the suburb had no wetlands, other than several run-off sumps.

A council spokeswoman said it would now test fertiliser levels before applications, gardeners would do training and the recommended season of fertiliser use was noted.

“Broadwet, a liquid soil wetter, and Biagra, a liquid water retention aid, is currently being used to maximise water use efficiency and the volume of product required, and minimal doses of a controlled, slow-release mini prill low phosphorous fertiliser is also being used,” the spokeswoman said.

She said an education program, possibly with other councils, would be investigated, water quality monitoring widened to storm water drains and basins, and controls on new buildings considered as part of development approvals.