The "Dunedin to Grey District Community Offering Fund" was opened at a function at the Otago Workers' Memorial in the city's Market Reserve.
Mr Cull said he had sent a message of support and sympathy to Grey Mayor Tony Kokshoorn after the second gas explosion at the Pike River Coal mine last Thursday.
"I was really quite touched by the response [to his message]," Mr Cull said.
"These messages really are very much appreciated."
He acknowledged that several appeals had been started since the mining disaster, but in this one, one part of the country was directly supporting another district in need.
The loss of 29 lives in the mine had left a "huge gap" in the Grey district community, and it was time to help, given the connections between all New Zealanders.
"We all care about other communities.
"We're not islands [as individuals].
"Communities aren't islands, either."
"It certainly brings that home to you," he said.
Donations to the Dunedin fund can be made in various ways, including at DCC customer services centres and at Westpac banks, through account 03 0905 0538315 00.
At the city council's finance, strategy and development committee meeting yesterday, Cr Paul Hudson asked whether the council would consider a contribution to the Pike River Mine appeal.
Chief executive Jim Harland advised Mr Cull could take the idea to the full council, which will next meet on December 13.
The Catholic Bishop of Dunedin, the Most Rev Colin Campbell, said the recent grieving in the Grey District over the mining disaster, and the empathy shown by many others around the country, reaffirmed the importance of relationships, family, and spiritual values.
Otago Southland Employers Association chief executive John Scandrett said he had asked the association's nearly 1500 members to support the fund.
Otago Chamber of Commerce chief executive John Christie said Otago had escaped recent disasters, and they should now support those "less fortunate".
Wenita Forest Products will hold another firewood sale, with profits going to families of the miners killed in the Pike River Coal mine disaster.
Wenita commercial manager Anne Horsewood said about 800 tonnes of radiata pine would be sold at its Mt Allan forestry block on Sunday, December 12.
The sale would run from 8am-3pm, with the location signposted from Salisbury Rd.
The wood would cost $10 to $20 for a single-axle trailerload, $30 for a double-axle trailer and $50 for a truck.
- Photo by Craig Baxter