The Royal Botanic Garden in Edinburgh has been forced to step up its security after thieves stole rare plants from its collection to sell on eBay.
Officials said the thieves must have specialist horticultural knowledge as it is their endangered plants that have been taken from the garden.
Now CCTV cameras are being installed at the world renowned scientific site.
Visitors to the garden are being asked to report anyone they see removing vegetation or cuttings from the garden.
Simon Milne, regius keeper of the Royal Botanic Garden Edinburgh, said: "We were noticing some plants were being damaged and indeed some plants being removed.
"We are pretty gutted, not just the fact we spend hours looking after these rare and threatened plants, it also undermines the very work we are trying to do, particularly in conservation, education and our scientific research.
"We are having to now up security measures here, one example would be to up CCTV and that sadly is diverting resources away from the conservation of plants.
"Our message to the public is if you see anyone vandalising plants, taking cuttings or removing them to please tell a member of staff."
Nigel Allman, who was visiting the garden from England, said: "I think it is appalling. They are just taking advantage of the work and effort that's been put into the garden. It's disgraceful really."