Although organisers were squeezed by rising prices, the $50 ticket price had not changed in the past four years.
This year's headline acts included "voice in a million" Eddie Low of Christchurch, chart-topping festival patron Dennis Marsh of Auckland, and New Zealand's best female country artist of 2010 and 2011, Tami Neilson. Mrs May said Australia's Royden Donohue and Aaron Jury of Kaitangata had also "gone down amazingly well".
A no-show by a headline act from Texas, The Gloria River Band, turned out to be a boon for fans of Kiwi country veteran Brendan Dugan when he stepped in to fill the breach. Mr Dugan was at the festival as a tour guide for Waikato country music fans but had not been expected to play.
"He's a legend. A lot of people still love him," Mrs May said.
Another highlight of the festival was Saturday night's surprise presentation of a platinum album to Dennis Marsh, whose Maori Songbook CD hit number one in the national charts last year and outsold 2011 releases by Lady Gaga, Katy Perry and Adele in New Zealand. Mr Marsh, whose iwi affiliations include Ngapuhi and Ngati Hine, is now New Zealand's best selling country musician of all time.
Mrs May said she was grateful to the Bay's accommodation providers, who put up the performers without charge, to the six venues, and to Fullers for providing free ferry transport for the musicians.
From August 10-12 Mrs May will organise her 20th Bay of Islands Jazz and Blues Festival, at which the same "use it or lose it" rule will apply.
"As long as the festivals are supported, and as long as I'm still standing, I'll keep going."
Both festivals brought large numbers of people to the Bay in what would otherwise be quiet off-season weekends. she said.
An economic development report for the Far North District Council in 2010 said the two festivals pumped $1 million a year into the Bay of Islands economy.