Eden Project co-founder Sir Tim Smit said he hoped the iconic attraction would "bounce back" in 2013 after a drop in visitor numbers and delays in new business forced the possible loss of up to 70 jobs.
The landmark attraction, which lost some 30 staff this time last year, confirmed on Monday that up to one in seven staff could leave as it looks to cut costs by £2 million a year.
Eden, which currently has the equivalent of 445 full-time posts, blamed a combination of poor weather, a successful Olympics and the ongoing recession.
"We have had another horror with the weather and we will, for the first time, come in just under the one million visitors mark," Sir Tim said yesterday. "In psychological terms that's a bit of a bruiser.
"We are hoping that the year was so exceptional, with such an amazing Olympics, that 2013 will be the year that we bounce back."
The environmental attraction, built for an initial £80 million, opened in a former china clay pit near St Austell in 2001 and is among the most successful schemes funded by the Millennium Commission.
But Sir Tim said they moved three years ago to create a more "mixed economy" at Eden, instead of being wholly reliant on tourist income.
That includes innovative new schemes such as HOW2 – an initiative with Cornwall College to develop a training facility to serve the emerging green economy. But he admitted that planned projects, which could create another 150 jobs and could yet absorb some of those facing redundancy, were 6-9 months behind schedule. In the next few months, Eden is also hoping to announce a deal in China which Sir Tim said would be a "wonderful portal into China for all the green technology we are promoting here in Cornwall".
With its combination of problems, Sir Tim said they had been forced to make the "sad" but "grown up decision" to cut costs and jobs.
But he said: "There would be nothing more damaging (to Cornwall) than having a blue riband project looking like it wasn't capable of being run properly."