After visiting the square, council parks manager Ian Maxwell said the grassed areas had become "worn and dusty", especially in areas of high use, and rubbish littered the area between visits by contractors.
The square, he said, was not equipped with automatic irrigation and the council's mobile irrigation efforts had been focused on sports fields.
After seeking more answers from the council, the council's communications team said the wrong information had been given to Mr Maxwell.
The square did have a manual irrigation scheme, but the grass had gone without irrigation for some time, said the central manager of local and sports parks, Jane Aickin.
She said the maintenance contract had changed in the past month from a streetscape contract to a parks maintenance contract carried out by council's city parks services.
Now that it was being managed as a park, higher service levels would apply, such as using fertiliser, turf care and watering, Ms Aickin said.
Heart of the City centre manager Tania Loveridge said St Patrick's Square was one of the city's little jewels.
"We would hope, given the level of investment, there is adequate and suitable management, particularly over the dry summer," she said.
The maintenance issue comes as the council is proposing to cut parks maintenance by 7 per cent in the new 10-year budget. Among the plans are less mowing of parks and replacing high-maintenance street gardens with low-maintenance ones.
City dust bowl
• $9.2m spent upgrading St Patrick's Square.
• No watering for some time.
• Summer heat has killed most grass.Paving and other areas looking untidy.
• Council has taken over contract with pledge for greater care.