The charity has also transferred 30 of its 90 staff to Webbs Garden Centres, which has taken over the retail, catering and conference Organic Enterprises arm of Garden Organic at Ryton, Warwickshire, which will now be known as Webbs Ryton Gardens.
Garden Organic may also be looking to outsource its administration to save money but a representative said there were no details available on this.
The representative said the restructure was a result of the current financial climate and dwindling research and development funding streams and "will affect both administrative and research posts". The charity could say how many people could face redundancy because it said some are likely to be re-employed in new projects.
It said Master Gardeners, Sowing New Seeds, Gardening Therapy and the LEADER project "will create several funded new posts at the charity's headquarters, Ryton Gardens, for which staff at risk of redundancy will be invited to apply".
The visitor attraction — Ryton Gardens — will remain under the management and ownership of Garden Organic.
Garden Organic's Chief Executive Myles Bremner, said: "As an organisation we have done all that we can to safeguard as many jobs as possible. These are difficult times and we hope that those staff affected will be redeployed in the new roles created through funding we have recently secured.
"We are hugely optimistic about our new charitable programmes and their ability to reach out to more people. At a more local level we are also excited about our developing relationship with Webbs, which will help secure the future of Ryton Gardens as a visitor attraction, helping place us in a stronger position to move forward with our aims to get more people in the UK gardening and growing sustainably."
Bremner said membership has stabilised at between 30,000 and 40,000 after declines of up to 1,000 a month earlier this year.
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