Sissinghurst has been a family house since 1930 when my grandmother, the poet and novelist Vita Sackville-West, and my grandfather, Harold Nicolson, the historian and biographer, rescued the house and garden from ruin.

My father, Nigel, handed it over to the National Trust in 1967, in lieu of death duties, but he was keen that his family should remain attached to Sissinghurst. Almost the last thing he said to me before he died was: “You will live here, won’t you?

I grew up here and I am sure I will be here until I die. For many years I had lived away but in 2004 I moved back with my wife and two daughters. We are members of what the trust calls the “donor family” and it is a strange role. Obviously the family has a deep emotional attachment to the place and everything about it is in our DNA. We could feel our way around every corner of it in the dark. But we don’t own it, pay for it, manage it, take any risks on it or any decisions on it. That is the strangeness – a commitment to something but with no control.

The trust has always liked the idea of resident families. It understands that a family that has a long association with a place has a feel for it that it is difficult to get in any other way.

Sometimes, it is true, the trust gets a bit stiff and needs a jollier and more spontaneous attitude to its properties. There is the story of two Norfolk houses – each with a grand piano in the hall. The notice on the piano in the trust house says: “Please don’t play the piano” but the notice in the other house says: “Please don’t play the piano for too long.” That just about sums up the difference.

All good places need the vitality that comes from a little elasticity and untidiness. A place’s authenticity needs to be allowed to breathe.

I think we have got quite a good system going. Everyone can see we live here with our girls and their friends running around with Frizzie the poodle, and Treacle, our labrador. But we try to engage as much as we can.

Sarah and I and my sister, Juliet, all give talks in the restaurant. We have been heavily involved in a project to grow food for the restaurant.

There are three key elements here: the trust, us and above all, the public. None of it would work without all three. And the place is reliant on the 130 volunteers.

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