Diesel prices are well above pre-war levels and unlikely to come down.
Agricultural businesses are being hit hard with increased costs of fuel, fertiliser and pesticides.
Rising transport costs could flow through to the rest of the economy and worsen inflation, according to industry experts.
The wheat and sheep farmer said the price of diesel, pesticides, herbicides and even shipping to his property just outside Wagga Wagga have all increased.
Crude oil has surged over $US105 per barrel, up from around $70 per barrel before the conflict.
For farmers like Mr Roles the pressures from the conflict in the Middle East look likely to continue, according to Commonwealth Bank head of commodities Vivek Dhar.
The war's closure of the Strait of Hormuz, through which a fifth of the world's oil normally flows, has left much of the world scrambling for commodities like diesel.
Mr Dhar said only about half the amount of crude oil from before the war is being exported from the Persian Gulf.
Refiners are not letting a crisis go to waste, with the profit margin per barrel, known as the "crack spread", increasing from around $24 to $69.
Australia is vulnerable to those price swings as it imports around 80 to 90 per cent of its diesel.
Mr Roles, who is also chair of the New South Wales Farmers Grain Committee, said "it's not like we can pass on these additional costs".
For the year to July prices rose at 3.6 per cent, the same speed as the previous month.