In a statement, the National Farmer's Union (NFU) said it was urgently calling on the Government to consider the introduction of a new student workers scheme, open to agricultural students from all over the world, to undertake seasonal harvest work.
Such a scheme would attract young people into the industry, bringing innovation, energy and skills that will help increase productivity on UK farms, the NFU said.
It said the results of the survey are the first demonstration that, since the ending of the Seasonal Agriculture Workers Scheme (SAWS) in 2013, growers are struggling to source an adequate supply of seasonal workers to meet their needs. Twenty-nine per cent of respondents said they experienced problems in 2015.
NFU president Meurig Raymond said: "The results of this survey are very worrying. Horticulture contributes £3billion to the UK's economy and employs around 37,000 people in England alone. However, a further 40,819 seasonal workers are needed every year in England to help grow, harvest and pack the produce. Harvest seasons with insufficient seasonal labour lead to British crops remaining unpicked, businesses facing massive losses and retailers being forced to fill shelves with imported produce.
"Putting a new student scheme in place will attract young people who will bring skills that can help increase productivity in the UK. This will help avoid labour shortages and the potential consequences of higher food prices, increased imports and loss of full time jobs that seasonal work supports.
"When SAWS ended, the NFU predicted it would lead to shortages in seasonal labour in horticulture as migrant workers move into other sectors of the economy. Our concerns were supported by the findings of the Migration Advisory Committee. These results show that, just two years after the removal of SAWS, growers are already experiencing major problems securing their supply of seasonal workers."
Businesses employing a higher number of seasonal workers experienced more problems, the labour-intensive fruit sector being most affected with 43 per cent of respondents experiencing problems last year.
The results also show that growers are anticipating these difficulties to intensify over time, with labour becoming more expensive and harder to find. 53 per cent of respondents expect an increase in labour costs this year, with this proportion rising to 84 per cent by 2018. In addition, 66 per cent of respondents envisage reductions in labour availability by 2018, with 43 per cent believing that this will result in their business experiencing labour shortages.