Owners of the garden centre are proposing to demolish the four existing buildings on site and replace them with one larger building, which would increase its retail floor space and create 15 new jobs.
The council said:
"The development will improve the state and age of the current building. This is a viable business, which is valued locally and it would be churlish to refuse it.
"They are going to great efforts to make the building as green as possible."
Currently 69 staff work at the garden centre.
Plans also include the creation of 85 more parking spaces, including disabled parking provision.
South Gloucestershire Council’s development control committee approved the plans last week.Park also has centres at Cheddar and Lechlade.