"That is the ultimate reason for supporting them - we are trying to improve New Zealand and it is just our small contribution.
"We're very much into supporting education and the cultural side of things and pragmatically, obviously, you hope that it rubs off and we become a better society as a result of it."
Mr Crombie says Diana "is very heavily involved in the trust - she is the one that does all the hard work behind the scenes".
He has been involved with Hawke's Bay Water Group for the past 12 years.
Mr Crombie also helped establish the Rose Charity Eye Clinic in Phnom Penh, Cambodia. The Clinic has become the leading eye clinic in Cambodia, assisting people in rural areas with sight difficulties.
He said he was "stunned but absolutely pleased and honoured to have been considered" for the QSM.
"I'm rather humbled that they considered me worthwhile, which is lovely."