Tennyson's phrase "red in tooth and claw" has long attached to Darwinian nature. Yet Darwin was always, and sometimes mainly, concerned with plants. As he explained in On the Origin of Species (1859), he meant the term "struggle for existence" to evoke not just starving animals in mortal combat, but plants fighting against the elements (drought, say) and against each other, competing for ground space for their seeds or for the attentions of seed-spreading birds.
Much of his knowledge of plants was acquired at first hand. The Origin is full of Darwin's botanical observations, some reporting experiments done in and around Down House, Darwin's family home from 1842. "In the course of two months, I picked up in my garden 12 kinds of seeds, out of the excrement of small birds, and these seemed perfect, and some of them, which I tried, germinated." Then there were the many botanical books that followed, describing Down-based studies over an extraordinary range, from reproduction in orchids (1862) to the role of worms in forming vegetable mould (1881).
Although the theme of Down House as Darwin's laboratory has been explored before, there is room for the focused treatment that Michael Boulter's book promises. Even Darwin specialists could do with something for the general reader that opens up Darwin's work with plants. Uncompromisingly fact-filled, tied to the Origin in sometimes hard-to-detect ways, the botanical books make large demands, as Darwin himself acknowledged. "An examination of their many beautiful contrivances will exalt the whole vegetable kingdom in most persons' estimation," he wrote of the orchids. "I fear, however, that the necessary details are too minute and complex for any one who has not a strong taste for Natural History."
Boulter, a palaeobotanist, seems, alas, to share Darwin's fear. Darwin's Garden never goes near the details of Darwin's research. The botanical books get at most a few broad-brush paragraphs each. The plants and animals studied at Down House disappear for considerable stretches, especially in the book's second half, where Boulter connects sundry aspects of Darwin's science with later developments.
Few readers, I think, will expect the discussion here of the platypus genome. The first half of the book is more conventional, briskly covering the standard biographical territory (Shrewsbury, Edinburgh, Cambridge, HMS Beagle, note-books, barnacles, pigeons, the Origin, aftermath), but with Down House intermittently in view.
Here, too, there are surprises. Uniquely, Boulter reckons that Darwin's "principle of divergence" - an idea by which he set great store, and which he understood as explaining diversity in lineages evolving under natural selection - came to him in a flash on seeing some hedge parsley while on a carriage journey to Down House. From sources undisclosed, Boulter gives a lot of implausible detail: when it happened; Darwin's shout of (yes) "Eureka"; his distressed coachman jumping down; why the lane-side hedge parsley, with flowers a different colour from the hedge parsley in Darwin's garden, so inspired him. For BBC Radio 4 listeners, in a segment broadcast on 1 July 2008 to commemorate 150 years since Darwin's species theory was publicised at the Linnean Society, Boulter even showed the programme's science correspondent where it happened ("Ah, here we are ...").
Myth-making and myth-breaking are the business of anniversaries. The story of Newton's apple has outlasted all attempts to dislodge it as myth; historians now study the myth, intrigued by what it reveals about discovery stories in our culture. Attempts to uproot Darwin's hedge parsley will prove likewise instructive. Watch for them, and for the first hedge-parsley pilgrims to Down House (now an English Heritage site). And wait for the book we still need on Darwin's garden.
Darwin's Garden: Down House and The Origin of Species
By Michael Boulter. Constable & Robinson. 320pp, £16.99. ISBN 9781845295998. Published 26 June 2008