There aren’t all that many books specifically about Hardy Geraniums but the handful or so that are available to buy are useful and some can be bought second hand at little expense.
It’s hard to pick a favourite because they all cover geraniums in different ways. Some are more technical, discussing the anatomy and taxonomy, some specifically cover species and cultivars, great for identification or deciding what to put where in your garden and others are more general, touching on a bit of everything and including tips and ideas on companion planting to propagation. I’ll find myself frequently cross referencing and searching through them all for the answer I need.
The pamphlet, Genus Geranium, written by Walter and Will Ingerwersen in 1945 is a modest dip (by today’s standards) into Hardy Geraniums. It might be small, but it is packed with botanical information about many of the different species and touches on individual cultivars here and there. Some spellings have changed such as Vlassovianum to Wlassovianum and Silvaticum to Sylvaticum but ultimately the information is just as relevant today. I especially like the description given to the Wallichianum species, “Typical G. wallichianum just misses being a good garden plant, which is a pity, as it comes into its own after nearly all the other Cranesbills have done their seasons work and are ripening seed or preparing for a lesser, autumnal blossoming. It awakes late in the spring and we have frequently wondered if it has succumbed to the rigours of winter, but it is just a late riser and appeared again when we had almost given up hope”. I have found this to be true of G. Salome also, relief flooding through me as one of my favourites geraniums pokes its head up and yawns a sleepy good morning.
My copy of Geraniums by Margaret Stone for the Hardy Plant Society is well thumbed and was invaluable to me when I first took on the nursery. As you may recall the nursery had been neglected for some months and most plants, almost 1500, had lost their labels, it was necessary to be able to accurately identify them.
Another point of reference that was extremely helpful in my time of need was the Geranium archive found on the Facebook page of the North Facing Garden. Nik is a geranium fanatic and has an extensive collection of geraniums that he catalogues, photographs and gives very accurate write ups.
My Book List:
Gardening with Hardy Geraniums by Birgitte Husted Bendtsen
The Gardener’s Guide to Growing Hardy Geraniums by Trevor Bath and Joy Jones
The Plant Lover’s Guide to Hardy Geraniums by Robin Parer (A series of books in association with Royal Botanic Gardens Kew)
Hardy Geraniums New Edition by Peter. F. Yeo
Hardy Geraniums by David Hibberd (A Royal Horticultural Society Wisley Handbook)
Geraniums by Margert Stone for Hardy Plant Society
The Genus Geranium by Walter and Will Ingerwersen, 1945