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Monographs and other books for the plant collector
By an Amazon.com customer
Hardy Geraniums: The Complete Guide to the GenusHardy Geraniums: The Complete Guide to the Genus by Peter Yeo
Buy used from: $12.48
Great book,  covering all the hardy Geranium species currently in cultivation. Not too many pictures, but many drawings and an excellent ID key.
Clematis: A Gardener's Guide to the GenusClematis: A Gardener's Guide to the Genus by Christopher Grey-Wilson
Buy used from: $1.43
The standard work on Clematis. Filled with beautiful pictures and notes, covering the whole genus.
A Guide to Species Irises: Their Identification and CultivationA Guide to Species Irises: Their Identification and Cultivation by Species Group of the British Iris Society
Buy used from: $564.60
The new standard work on Iris. Unfortunately quite expensive.
The Genus IrisThe Genus Iris by William Rickatson Dykes
Buy used from: $6.98
Was the standard work on the genus for any years, but is a bit outdated.
Iris of ChinaIris of China by James W. Waddick
Buy used from: $6.25
Good book, covering all Chinese Iris species.
TrilliumsTrilliums by Frederick W. Case
Buy used from: $25.99
A great Trillium monograph, the only Trillium book you'll ever need.
The Gardener's PeonyThe Gardener's Peony by Martin Page
Buy new: $29.16 / Used from: $15.95
The Genus PaeoniaThe Genus Paeonia by Josef J. Halda
Buy new: $23.07 / Used from: $8.99
Already a bit outdated, but a good book for the collector. Illustrations are not useful for identification purposes.
The Genus Epimedium and Other Herbaceous Berberidaceae (A Botanical Magazine Monograph)The Genus Epimedium and Other Herbaceous Berberidaceae (A Botanical Magazine Monograph) by William T. Stearn
Buy used from: $129.99
A great book with beautiful illustrations, covering all herbaceous Berberidaceae.
The Genus Cypripedium (Botanical Magazine Monograph)The Genus Cypripedium (Botanical Magazine Monograph) by Phillip Cribb
Buy used from: $293.99
The Genus Arisaema: A Monograph for Botanists and Nature LoversThe Genus Arisaema: A Monograph for Botanists and Nature Lovers by Guy Gusman
Buy used from: $34.96
An excellent book, filled with pictures, illustrations and cultivating advice. All species covered.
Lilies: A Guide for Growers and CollectorsLilies: A Guide for Growers and Collectors by Edward Austin-McRae
Buy used from: $19.50
The Lilies of ChinaThe Lilies of China by Stephen G. Haw
Buy used from: $24.99
Another good book, covering all Chinese Lilium species. Includes very useful cultivation advice for each species.
Lilies: A Revision of Elwes' Monograph of the Genus Lilium and Its SupplementsLilies: A Revision of Elwes' Monograph of the Genus Lilium and Its Supplements
Buy used from: $71.93
Poppies: A Guide to the Poppy Family in the Wild and in CultivationPoppies: A Guide to the Poppy Family in the Wild and in Cultivation by Christopher Grey-Wilson
Buy used from: $30.75
Pulmonarias and the Borage FamilyPulmonarias and the Borage Family by Masha Bennett
Buy used from: $4.28
Genus PleioneGenus Pleione by Phillip Cribb
Buy used from: $22.20
Corydalis: a Gardener's GuideCorydalis: a Gardener's Guide by Liden
Buy used from: $57.38
Cyclamen: A Guide for Gardeners, Horticulturists and BotanistsCyclamen: A Guide for Gardeners, Horticulturists and Botanists by Christopher Grey-Wilson
Buy used from: $35.00
The Crocus: A Revision of the Genus Crocus (Iridaceae)The Crocus: A Revision of the Genus Crocus (Iridaceae) by Brian Mathew
Buy used from: $195.70
The standard work on Crocus, unfortunately very hard to find and a little outdated. Isn't it time
HelleboresHellebores by Brian Mathew
Buy used from: $490.59