"The more you irrigate, the more vegetative growth you will get, rather than the generative growth you want," he told the meeting.
"Growers' mistakes are made in the dark, mild, 'vegetative' days of February to April. Botrytis is also correlated with rate of irrigation in the first eight weeks. Even in propagation, the longer a grower can go between irrigation, the more generative growth you get."
But he added: "It's difficult to over-irrigate in summer, when the danger is that your irrigation capacity is too low."