Income generated from NGS garden visits in 2012 was seven per cent down on 2011, which compares favourably with many other gardens open to the public.
Morley said ahead of the NGS Yellow Book launch last week: "We were satisfied with what we achieved in terms of the amount of income we generated from garden visits considering the tales of woe from garden-related visitor attractions. It was pretty bleak for them."
Net garden income for 2011 was £3m with around £550,000 coming in from other sources. Some £2.6m was donated to beneficiaries.
Some £2.1m of 2012's £3.3m income will be donated. Net garden income was £2.7m.