Nixon was speaking after it emerged that some National Trust gardeners were still buying plants grown in peat. Discussing the continuing difficulties of finding local peat-free plants, Nixon said: "If push comes to shove we are clearly going to have to make some very difficult decisions. We are not moving away from our policy but there will always be challenges."
Asked if that meant the trust would have to stop growing certain varieties Nixon said: "Yes, it is conceivable. I am looking from the overall perspective of conservation so it is not entirely for me to say, but if the situation calls for it that is an option."
The National Trust has had a peat-free policy since 2001, which demands that all plants grown in or sold at trust properties would be raised in peat-free compost except in "exceptional circumstances", such as raised peat beds and ericaceous plantings integral to the history of the site.
Despite this, Hill House Nursery owner Raymond Hubbard told HW that he continued to sell plants grown in peat-based compost to National Trust gardeners.
Hubbard said: "We grow in peat and we have three or four National Trust gardeners that come to us and they buy quite a lot of plants. They buy an awful lot of bananas, all of which are grown in peat-based compost. I don't think there (are enough) people growing things in non-peat compost.
"If you wanted to buy an entire range of peat-free plants, you would find it very difficult."
Nixon said the policy was not designed to make life difficult for National Trust gardeners and that he hoped the revelation could start a dialogue to find solutions.
He said: "I'm obviously concerned but I'm not distraught. It is a difficult situation and what we are interested in is dialogue, not conflict. No gardeners should be using peat; its importance has been underlined by the climate change issue because peat is an incredibly important carbon store.
"If we do not work to find solutions and technologies that can allow us to grow without peat, it will have an impact on all gardeners."
But Hubbard emphasised the problems that remain in changing consumer tastes. He said: "We stocked peat-free compost for a while and we ended up selling it two for the price of one. The customers just don't want it."
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