Book of the Month for Oct 2023

Dionysia (Primulaceae) the Cusion Primroses
Joseph Tychonievich

Dionysia (Primulaceae) the Cushion Primroses Magnus Lidén and Iraj MehreganActa Universitatis Upsaliensis, 2023

Dionysia is one of the most desirable genera for many a rock gardener, but this book explores the genus not in cultivation but in the wild. Flip through the pages and you won’t see many photos of perfectly grown Dionysia filling their pots with a carpet of brilliant flowers, but rather, countless images of them growing in the wild, as well as things like scanning electron microscope images of farina-secreting trichomes. This book is a beautifully photographed, exhaustively researched, clearly written academic monograph.

The first forty or so pages detail the morphology, taxonomy, habitat, breeding systems, and history of the genus. This is by way of introduction to the bulk of the book which details, over the next nearly 200 pages, each species of Dionysia with thorough descriptions of their morphology backed up by multiple photos, usually showing close-ups of flowers and foliage as well as pictures of the plant growing in habitat.

It is hard to overstate how impressive the photography is in this book. Sixty-four species are profiled, many of which have small wild populations growing on difficult-to-reach cliff faces. The amount of work that went into photographing them all is truly astonishing.

The very last section chapter of the book is a brief, four-page, discussion of growing Dionysia in cultivation, detailing the methods used to cultivate these plants at the Gothenburg Botanical Garden (Göteborgs botaniska trädgård) in Sweden. Most gardeners in North America will need to do some adjusting to translate this into their local climates, but much of the information is universal and extremely helpful, with excellent photos showing methods for rooting cuttings, soil mixes, and growing on tufa.

This is not a book aimed at gardeners, and if you are simply looking to crack the code on growing a perfect, flower-covered Dionysia, this is not the book for you. It will be an invaluable reference for anyone botanizing in parts of the world where Dionysia grow wild, a necessary addition to the library of any lover of the genus, and a beautiful book to page through and wonder at the sheer beauty and diversity of the genus Dionysia


.Joseph Tychonievich is the Editor of the Rock Garden Quarterly. This review originally appeared in the Fall 2023 issue and is reprinted here with permission. Joseph lives and gardens in South Bend, Indiana.