The National Party has retained most of its rural vote, after being re-elected to Government at the weekend.
David Carter says he hopes to stay on as Minister of Agriculture.
National won all its rural electorate seats except for West-Coast Tasman.
Labour's Damien O'Connor, the party's agriculture spokesperson, has taken back the seat after beating current MP, National's Chris Auchinvole, by more than 2000 votes.
Meanwhile, Mr Carter says he will know within a week if he is to continue as the Minister of Agriculture, Forestry and Biosecurity.
He says he will express his wishes to do so at a cabinet meeting later this morning.
"I think there's a lot of unfinished business with regards to water, making sure we get a very sensible emissions trading policy."
Mr Carter says he will push for more irrigation of farmland.
"We've now started a lot of work on water. I want to actually see some increased areas of irrigated land."
Mr Carter says it is also vital to ensure constant reviews of New Zealand's biosecurity arrangements at the border.
"The downside if we get a major incursion in this country is just huge. So we do need to concentrate on getting the best biosecurity systems in the world."
Nicolson not placed
Former Federated Farmers president and ACT candidate, Don Nicolson, who was No 3 on the party's list, has missed out on a seat in Parliament.
Although the party won the Epsom seat, its share of the party vote was too low to allow it to bring in any other MPs.