University of Oxford Botanic Garden - Walled Garden

Walled Garden

• Botanical family beds

The core collection of hardy plants are grouped in long, narrow, oblong beds by botanical family and ordered according to the classification system devised by nineteenth century botanists, Bentham and Hooker. The families represented in the Walled Garden include: Acanthaceae, Amaranthaceae, Amaryllidaceae, Apocynaceae, Araceae, Aristolochiaceae, Berberidaceae, Boraginaceae, Campanulaceae, Caryophyllaceae, Chenopodiaceae, Cistaceae, Commelinaceae, Compositae, Convolvulaceae, Crassulaceae, Cruciferae, Cyperaceae, Dioscoreaceae, Dipsacaceae, Euphorbiaceae, Gentianaceae, Geraniaceae, Gramineae, Hypericaceae, Iridaceae, Juncaceae, Labiatae, Leguminosae, Liliaceae, Linaceae, Loasaceae, Lythraceae, Malvaceae, Onagraceae, Paeoniaceae, Papaveraceae, Phytolaccaceae, Plantaginaceae, Plumbaginaceae, Polemoniaceae, Polygonaceae, Portulacaceae, Primulaceae, Ranunculaceae, Rosaceae, Rubiaceae, Rutaceae, Saxifragaceae, Solanaceae, Umbelliferae, Urticaceae, Verbenaceae, Violaceae.

In 1983, The National Council for the Conservation of Plants and Gardens (NCCPG) chose Oxford Botanic Garden to cultivate the national collection of euphorbia. One of the rarest plants in the collection is Euphorbia stygiana, with only ten plants left existing in the wild. The Garden is propagating the species as quickly as possible to reduce the possibility of it becoming extinct.

• Economic beds

Eight beds in the southwest corner of the Garden represent plants with links to modern medicine. Examples include Galega officinalis which contains galegine and guanidine, upon which the anti-diabetic drug metformin is modelled and Artemisia annua which is the source of the anti-malarial drug artemisinin.

• Variegated plants

Two beds in the northwest corner of the Garden contain variegated plants laid out according to the classification system devised at the Garden by Professor C. D. Darlington and former Superintendent J. K. Burras in the 1970s. Examples include Aegopodium podagraria 'Variegatum', a highly invasive plant introduced in the Middle Ages as a potherb boiled like spinach, and used in the treatment of gout; Weigela praecdox 'Variegata', a compact shrub suitable for a small garden; and Cornus alternifolia 'Argentea' known as the pagoda dogwood.

• Hybrids and parents

One bed in the north end of the garden contains some hybrids between species from the same genus. An example includes Viburnum × bodnantense, growing with its parents, V. farreri and V. grandiflorum.

• Bearded irises

One bed in the northwest corner of the garden contains a display of bearded irises each May. Examples include Iris 'Eileen' and Iris 'Golden Encore'. Some of the varieties grown in the Garden are not grown anywhere else.

• Wall borders

The borders along the foot of the wall contain collections that thrive in the microclimate created by the Wall. The cool east border includes ferns, Stachyurus praecox, Astrantia major, and Equisetum telmateia. The dry, shaded south border includes Jasminum nudiflorum, Hydrangea anomala petiolaris, Lonicera fragrantissima and L. × purpusii, and the unusual and rare Ercilla volubilis and Arisarum proboscoideum. The southeast border contains the bamboo collection.

The west and north borders contain plant collections grouped by their geographical origin. The Sino-Japanese collection at the southwest border includes Clerodendrum bungei. The North American collection at the west border includes Fremontodendron californicum. The European collection at the northwest border includes Cliantus puniceus. The Mediterranean collection at the north border includes Euphorbia myrsinites. The South American collection at the north border includes Acca sellowiana. The South African collection at the northeast border includes Kniphofia caulescens.