When I began my first garden 40 years ago in a village near Oxford, the cottage where we lived had one cold tap and an outdoor lavatory and the ceilings sagged with damp; but the ground outside was rich and black from 500 years of digging and the accumulated silt of millennia of flooding. And, almost as important, across the water meadows on the other side of Oxford was Waterperry, where Beatrix Havergal, Miss H as she was universally known, had set up her Waterperry School of Horticulture for Ladies in 1928. Waterperry was where I first tasted an Ashmead's Kernel apple, bought my first blackcurrant bushes and fell in love with phlox. It never occurred to me that horticulture could ever be thought an unsuitable job for a woman.

But it had been a long, hard fight. The struggle for women to gain access to training and careers in professional horticulture is the last and longest section in Catherine Horwood's multi-layered Gardening Women, but it is the thread which binds the whole together. Waterperry was one of the most famous and longest-surviving of the private training establishments, but it was not the first: Swanley in Kent (later amalgamated with Wye College, itself now subsumed in Imperial College, London) opened its doors to women in 1891, and by the early years of the 20th century there were more than 20 such schools turning out pupils who regularly topped the RHS examinations.

But after training, the problem was still where to find work  and what to wear. The first female gardeners taken on at Kew in 1896 (dubbed the "Kewriosities" by the London press) were attired in bloomers. When passing omnibuses were crowded with rubbernecking sightseers and songs were published with such refrains as "Who wants to see blooms now you've bloomers at Kew?", the girls were quickly told to wear knickerbockers (not trousers) instead.

Trained "lady gardeners", were something new. But "weeding women"  that legion of lower-class, poorly-paid female workers  had always been a presence in gardens: in 1530 a nameless pair in the archives of Cardinal Wolsey's Cardinal College (later Christ Church) were paid a total of 16d for three days' work "rooting up unprofitable herbs in the garden". Country women too, of course, had always tended their own gardens, raising the medicinal and culinary herbs and plants required by their stillroom recipes. But they are rarely remembered in their capacity as gardeners, and Horwood skates over the earlier centuries to open her multiple biography of British women and their varied gardening activities with women whose names emerge in the 17th century.

Horwood divides her biographees into six sections: plantswomen, designers, vegetable growers, painters, writers and working gardeners, each section traversing the period from 1600 to the present. Immediately this makes for confusion, with many of the women belonging in several sections. Thus the section on plantswomen begins with Thomasin Tunstall, the "courteous Gentlewoman" who supplied Parkinson with a white hellebore in the 1620s, and proceeds via Mary, Duchess of Beaufort and Ellen Willmott to Beth Chatto and Jekka McVicar, via three dozen or more others in between. What's the link? There is the glimmer of an idea  the sense of a laying on of hands  but it remains undeveloped. A more serious problem is the sheer number of people: however well-meaning the enterprise in seeking to rescue these women and their achievements from oblivion, the biographical detail is frequently so sketchy that many of the women fail to emerge as individuals at all.

Presumably it is lack of space, too, which prevents the greater use of archive sources (though occasionally Horwood strikes gold, as in the papers of Chrystabel Procter, gardener at Girton College, Cambridge, from 1933 to 1945), and it is disappointing that the passages on some of today's most influential gardening women, such as Beth Chatto, Carol Klein, Sibylle Kreutzberger and the late Pamela Schwerdt, are regurgitations of already published material, specifically the first-person accounts included by Tessa Traeger and Patrick Kinmouth in their 2003 book A Gardener's Labyrinth.

This is a pity. There are some wonderful stories here, but I wanted more colour  both in the showing as well as the telling: the illustrations are confined to a handful of murky black and white photographs, with a measly selection of eight colour plates presented as a centre section. More paintings, more photographs  of the women themselves and the plants they cherished  more vividness in the telling of their lives, would all have made this a better book.

Katherine Swift's The Morville Hours: The Story of a Garden is published by Bloomsbury.