Mrs Capper, who grows apples and hops, will serve as chair for a further two-year term.
She is joined by Derek Wilkinson, who has been elected to the board as vice-chair. He grows spring onions, asparagus and legumes for retailers.
Mrs Capper said: “I am delighted to have been re-elected as the horticulture and potatoes board chair and I want to thank the board for their support.
“The horticulture and potatoes sector is extremely efficient, productive and innovative, and the next two years will be absolutely crucial as we deal with the UK leaving the EU.
“We need to make sure that we have access to a competent and reliable workforce in order to continue delivering food for the nation. As a team, we will be working extremely hard to get the best deal for growers."
Mr Wilkinson said: “I am very pleased to be elected as vice-chair of the board, particularly at such an important time for the sector.
“I’m looking forward to working with Ali and the wider team over the next two years and I am delighted to have the backing of the board.”