London's Royal Botanic Gardens, Kew suffered an 8.5 per cent fall, dropping from 13th to 15th place in the visitor numbers league. Visits to its Wakehurst Place outstation dipped by 5.9 per cent.
Meanwhile, Cornwall's Eden Project saw visitor numbers decline by 3.1 per cent. However, the RHS flagship garden at Wisley gained two per cent.
Britain's top 10 attractions, of which nine are free, together saw a 2.9 per cent increase in visits.