"There has been a great deal of waterlogging since mid December, with many orchards saturated," he said. "That's likely to give an increase in diseases, especially canker."
Similar wet conditions in 2012 caused "quite significant tree losses", he added. "The worry is that we will have similar or even greater losses now. The longer this wet period goes on, the greater the risk."
The lack of frosts so far is a further concern, said Barlow. "It means trees aren't shutting down properly so they won't have much vigour when they come back to life in spring and you won't get the quantity and quality of buds you would hope for, which will of course adversely affect the subsequent crop. None of this is definite yet, but we are slightly nervous."
But January has proved to be a bumper month for English apple sales, he pointed out. "We have had a terrific start to the year, with sales to the multiples in the first three weeks up 14 per cent on January 2012, which was a good year, and up 24 per cent on the same period last year."
Thanks to the late start to the season last year and "a strong garden crop" that reduced pre-Christmas sales, there are now plentiful supplies of a range of UK-grown varieties, he explained.
"There is a lot of strong promotional activity but there has to be balance on pricing to give growers enough return to reinvest."
Meanwhile, on the field vegetable side, vegetable consultant David Norman said: "It's a couple of weeks until any land work will be done so it's a bit early to say. If it's still as wet in a month's time then it will be an issue."
Brassica Growers Association chairman Matthew Rawson added: "With the end of the season now in sight, it just makes the job a bit more challenging."
"Wet conditions have continued to add to already saturated land, with many fields needing considerable time to dry out before land work is possible. The earliest growers will be starting planting on the lightest land when conditions allow."
The Potato Council