Prolonged dry periods last winter and early this spring, coupled with the wet summer have put the arboretum’s collection of 1600 trees and woody plants under stress - but may lead to amazing winter colour.
Batsford's head gardener Matthew Hall said almost constant heavy rain and grey weather over past three months have been very trying for staff and visitors, with the arboretum suffering from waterlogging.
However, he said conditions should result in a better than normal autumn.
"The incredibly wet summer means the trees have put on a huge amount of growth during the summer months after a period of stress last winter and early this spring when trees suffered from the dry weather," he said.
"The extra growth spurt means the trees have built up more sugars in their leaves, so if the weather is right, with warm days, cool nights and light winds, we should be in for a really good autumn."
He said the Japanese maple collection would be the stars of the show.
"We’re all really excited about the prospect of a good autumn at Batsford and want as many people as possible to come along to experience the magical colour," he said.