Was there was any particular book that nurtured your interest? Your first choice is Simon Schama’s Landscape & Memory.

Books like Landscape & Memory came after I got interested but it was a book which expressed in black and white the hunch I had: it was there, laid out so beautifully, because Simon Schama has this talent for taking little stories and placing them in a broad context. I read it ages ago but the one chapter that has stayed with me most vividly is the one about mountains. He describes the journey humankind has taken in relation to their perception of mountains, which started as something really horrid and scary, so that in the early 18th century tourists who crossed the Alps drew their blinds to avoid seeing the horror of the mountains. They would literally blindfold themselves. Then in the later 18th century there’s the whole idea of the sublime, that you find God in the mountains as an awesome, glorious expression of God’s might. And then there’s the chapter on the Teutenwald, the idea of barbarian wilderness as viewed from the Roman world of classical order. When we look at the shift in the relationship between man and nature, that’s what really interests me. If you look at the medieval garden - the hortus conclusus - it shuts out the wilderness. The wilderness is something scary so you put up walls and create this very manicured little paradise and then with industrialisation and more people moving into the city, more people losing their direct relationship with nature, suddenly nature in its wildness becomes celebrated. So you have the ha-ha for example, where, instead of putting up a wall to protect your garden, you dig a ditch. You have the same security because the cattle can’t come in but you can look over the whole landscape: you invite the wilderness into the garden. And it’s a continuing process. In a very simplistic way you could see how people respond to threats to the environment by planting wild meadows in their gardens. I’ve found Landscape & Memory one of the most extraordinary books of cultural history I’ve ever read and it certainly seems to be one that has set all sorts of hares running.

Another of the books you’ve chosen is Tim Richardson’s The Arcadian Friends, which concerns perhaps the most eminent of Britain’s landscape gardeners, Capability Brown. 

Well, I see it slightly differently. For me The Arcadian Friends is a brilliant book because Richardson does two things. For one thing he really knocks Capability Brown off his green throne. It really is inexplicable how Brown has become the hero of British landscape garden when, in fact, he destroyed quite a lot of landscapes. He must have been a very good promoter of the services he provided in order to achieve that status. So I adore the book for its relentless demolition of Capability Brown, because he really annoys me so much. So that’s a large part of its appeal. But what he does very brilliantly, unlike any other garden historian I know, is that he doesn’t only consider the pretty landscape and plants. He really understands that in the 18th century the landscape garden was a canvas to express your political beliefs. There are two elements to it. He explains the difference between a Whig and a Tory garden and he also brilliantly shows how landscape was the only way disgraced politicians could express their power. He begins with the Glorious Revolution, saying that before then all gardens were imitating French gardens. He then looks at how after the Whigs in Britain invite William III to take the throne, instigating a constitutional monarchy, French gardens can no longer be countenanced because they express French absolutism. These French gardens have avenues that cut through the landscape. Everything is formal. There’s this corset of patterns you impose on nature. Here I am, the King: I can subjugate. After the Glorious Revolution they stop clipping their trees and it becomes a symbol of liberty, at a time when England was seen as the seat of liberty. 

This is the moment when Britain is on the cusp of becoming an imperial power. How does horticulture reflect that colonialism and that expansionism?

The Empire becomes really important in terms of the plants in the garden. You have someone like Joseph Banks who sees the Royal Botanic Garden at Kew as the engine of colonial growth, the storehouse of the Empire. His idea was to bring potentially lucrative plants from all the colonies back to England, to test them, propagate them, experiment with them at Kew, and then send them out to other colonies. For example, it was Banks’s idea to bring tea plants from China to India, though it’s not until 40 years later that it finally works. But let me give you an example too of how Banks used his horticulture to project values in visual form. In the gardens at Stowe House that he designed there are temples in the gardens that are literally a manifesto of his political beliefs. You have a ‘Temple of Modern Virtue’ and a ‘Temple of Ancient Virtue’, which is built as this flawless classical temple with statues of all the Greek thinkers in it, because Banks and his friends all believe that the Roman and Greek Republics represented virtuous civilisation. 

At that time Robert Walpole was the Prime Minister and was criticised by the country Whigs for being debauched, for having too much power, for being too close to court. So Banks builds a ‘Temple of Modern Virtue’ deliberately as a ruin to show how bad modern virtue has gone and, to ram it home, he puts in a headless statue of Walpole in modern dress. We’ve forgotten how to understand this language: we see the building as a pretty ruin, but to the aristocratic visitor of the day all these things would be understood as political satire. That effect starts at the gate to the garden, where you have to choose between the Path of Vice and the Path of Virtue, which is the choice of Hercules, so they’re taking Greek myths, placing them in the garden and applying them to modern politics. Everyone understands it. When John Adams and Thomas Jefferson go to Stowe they talk about the garden in that way, and they love it because they view in it an expression of liberty: actually, they go a step further in interpretation, seeing in it symbols of debauched England and the virtuous America.

We’ve talked about how the trade in plants and the attempts to propagate them across the Empire presents a benign perspective on colonialism. In America, of course, Jefferson and Adams saw a very different side of it. Is that your primary interest in Joseph Ellis’s Founding Brothers, or is it more an interest in how it structures history?

Ellis wrote this quite small book, Founding Brothers, for which he won the Pulitzer, I think. And he’s very bold and brave because what he does in looking at the period just after the American Revolution is, instead of writing a massive 700-page book, he just gives you seven events which will tell you everything you need to know. So, in terms of narrative structure, it’s a great book. One example he takes, that he titles ‘The Dinner’, is a dinner party hosted by Thomas Jefferson for James Madison and Alexander Hamilton in June 1790. At the time Madison and Hamilton were at complete loggerheads about two things: one is the financial plan that Hamilton is proposing as the Secretary of Treasury, which is all about very close financial and trading ties with Britain, and which Madison, as a Virginia planter, hates. Then, on the other side, there’s the big question of where the new capital of America is going to be. The northern states want it somewhere like Philadelphia or New York, which have commercial ties, and the southern states don’t want that because at that time the 13 states are only just growing up from being a war alliance and are concerned that the United States will become a mercantile country rather than an agrarian republic. So there’s this ongoing struggle between the two men and Jefferson brings them together at this dinner party over lots of French wine and good food cooked by the French cook and they reach an agreement whereby Madison agrees to accept Hamilton’s financial plan, if he will accept that the capital will be in the middle of nowhere, a place which will become Washington DC. So what Ellis does is take this one moment and cast it as a narrative device. 

Other events include the duel between Aaron Burr and Hamilton, the friendship between Adams and Jefferson, Washington’s farewell address, which he really spins out. I think that’s a brilliant way of getting into big history: through small moments. I do think that there are paradigms in these kinds of moments that we can only see in hindsight and it makes a very effective way of telling a story.