The current SAWS is due to end this year, though it may be extended to 2013.
The NFU says that, post-2013, it wants a scheme that will combine an ongoing supply of migrant labour with incentives to encourage UK citizens to take up work in the sector.
NFU deputy president Meurig Raymond said: "SAWS has helped growers to overcome employment difficulties by providing an ideal contribution to the industry's seasonal labour requirements for the past 60 years.
"It's a top priority for the horticulture sector to secure the continued availability of seasonal migrant labour when the current SAWS arrangements end."
He added: "We are also proposing a combination of training initiatives and welfare benefit adjustments that will challenge the perception of horticulture as a place to work, and encourage inactive citizens into a sector job."
In May, a report by the Independent Farming Regulation task force described the adequate supply of seasonal labour as "critical, particularly for horticulture", and called for some form of SAWS to be retained.