Speaking at the British Crop Production Council congress in Glasgow, research scientist Rosemary Collier gave an update on Defra and Horticultural Development Company (HDC) funded research on the impacts of climate change on horticultural crops.
As well as new data on the effect of changing climate on pest and disease threats, the study considered how it might affect soil.
Discussing the new findings, Collier said: "We had not anticipated the impact climate change would have on soil conditions and how significant that would be. But if growers cannot plant at the right time it throws everything out."
She explained that because increasing winter rainfall and summer heat would change soil conditions, land preparation, sowing and harvesting times might all have to change.
The study, led by Professor Brian Thomas, used the latest UK Climate Projections (UKCP09) modelling data. It found that climate change has a range of impacts on pests and diseases that will have a major effect on growers.
Summing up the study so far, Collier said researchers would be able to predict trends to some extent, but day-to-day weather would still have a big impact.
She added: "In the main, life is going to get harder for growers because their greatest challenge is the weather and we still are not very good at forecasting it."
She warned that the diamond-back moth (Plutella xylostella), a worldwide pest of Brassica crops, poses an increasing threat in a changing climate.
The moth completes its life cycle more rapidly in warm weather, meaning that our predicted hotter drier summers could lead to more generations and more damage per season.
The researchers raised concerns over whether the moth could survive winters in the UK. The changing weather would also have a negative impact on the number of cutworms (Agrotis segetum) surviving, according to the data. But there may be positive as well as negative effects, Collier suggested, citing the likelihood that potato lifting will benefit.
The team of four researchers, which includes Dr Steven Adams, and Jane Fellows, will continue to look at the many ways climate change will affect horticulture.
But because UKCP09 does not offer models for factors such as wind speed, humidity and leaf wetness, Collier said the true impact of climate change on horticultural crops was impossible to predict.
The project started three months ago and is due to conclude in the spring, when its findings will be available through the HDC.