The gardens include impressive fountains
The Duchess of Northumberland has hit back at claims that her Alnwick Gardens are a drain on public funding.
The gardens are under restoration before the second phase of work begins, but critics in the south of England have called the project "vanity gardening".
The latest attack, in an article in The Spectator magazine by Lady Mary Keen, criticised the amount of public subsidy that the Duchess was seeking.
Lady Mary, daughter of the 6th Earl Howe questioned whether Alnwick deserved such public investment.
"Should those who are savvier and nobler than thou attract so much more money than those who are perhaps more deserving?" she wrote.
But the Duchess has said the attack is caused by jealousy that the gardens are in the North and not the South.
She said: "There has been a campaign of sniping going on for some time in the South - it began because I went to Europe to find my designers. I wanted to find the best there was and that was in Europe.
"I felt I have put my head above the parapet and am now being shot at.
"There was always annoyance that I had not built it in Surrey or elsewhere in the South, but decided to build it in the North.
"Yet there was a perfect derelict site available at Alnwick to build the garden. We know what we have done is of great quality.
"This garden does not belong to us, we have given it over to a public trust."
She said the garden had not had any local public funding but the first phase had been built with a grant from the Duke.
Now she is seeking £16m of public funds to develop more of the Northumbrian countryside into a "modern garden" which she hopes will bring jobs and prestige to the north.
There are more than 65,000 flowers and shrubs planted, with varieties of plant from across Europe.
The central attraction of the garden is a cascading water feature, which curves and courses between trees and shrubs.
Leading Belgian garden makers, Jacques and Peter Wirtz, designed the 26-acre site.
The Duchess was given the land, a former 18th-century walled garden, by her husband, the Duke of Northumberland, when he inherited the estate in 1995.
She was also given £5m for the project by her husband.
The charitable Alnwick Garden Trust has raised £1.2m, of which £800,000 was awarded by One North East, the regional development agency, and £450,000 came from European funding.
The second stage of the project, which begins next month, will last 18 months.