Mr Muller said the Bay's horticultural sector was going from strength-to-strength, providing the region with more jobs and higher incomes.
"This agreement secures the long-term future of Bay exporters to Korea," he said.
"I strongly support free-trade agreements, such as this one with Korea, for the benefit of getting Bay growers better access into Asian markets.
Mr Muller said the agreement would also make possible a new level of co-operation in areas like agriculture, the creative economy, the environment and education, and spur greater investment.
The FTA offers improved protections for New Zealand investors in the Korean market, and reinforce the attractiveness of New Zealand as a stable investment destination, he said
New Zealand Kiwifruit Growers Inc president Neil Trebilco said the FTA was not just good news for the whole kiwifruit industry, of which about 80 per cent of growers were based in the Bay of Plenty region, but also the country's primary industries as well.
"It is certainly good news for our growers," he said.
Mr Trebilco said for some time New Zealand had a free trade agreement with China resulting in huge benefits, including about $10 million across the whole kiwifruit industry.
New Zealand paid $20 millions in duties to Korea last year across the industry and if 45 per cent of that came back over the next five years that would create significant savings of about $3 million a year, he said.
Mr Trebilco said Chile also sells kiwifruit to Korea and under its FTA with Korea, didn't pay any duty this year so this FTA was "really important" .
Korea was our fourth biggest market after Europe, Japan and China, he said.
Removing the tariff was the equivalent to putting $8500 in the pockets of the average kiwifruit grower every year, Tauranga MP Simon Bridges earlier said.