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Lawn fungus

We have new Ready Lawn down and with the warm, wet weather we are having in Tauranga patches in our lawn display purple/grey crystal-like formations on the grass which turn black overnight. Prior to this the lawn was very green and healthy and has been well fertilised with Yates lawn fertiliser and also watered with Thrive earlier in the year. I have sprayed the lawn with Yates Greenguard but the problem is still visible.


Your lawn has a fungal disease which has proliferated because of the warm, humid weather we have experienced recently. This can be controlled by spraying with Fungus Fighter or Bravo. Repeat spray every 14 days to make sure you control the fungal disease. You will find, as the weather cools, it will be less prevalent.

Reduce the amount of fertiliser applied to the lawn, especially in winter. Fertilisers high in nitrogen cause fast growth which will be soft and more likely to result in fungal diseases in warm, humid conditions. Reduce watering at this time of the year, and adjust according to the weather.

UnitecAdvice by Dr Dan Blanchon from Unitec's Diploma in Sustainable Horticulture and Bachelor of Resource Management.

Reproduced with permission from NZOOM Home and Garden content,
from the previous website of  TVNZ News

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Last updated: June 27, 2005