National will give farmers another $13 million a year to adopt more environmentally friendly methods.
Leader Bill English said a fund for sustainability farming, now called the Future of Farming Fund, would get $20m a year if National was in government - up from $7m a year.
It would help farmers and food growers to develop technology such as soil sensors and plants with higher yields.
Speaking at a horticulture factory near Levin, English said National's co-operative approach was a contrast to Labour's policies, in particular its water tax.