Autumn/Winter 2011/12 - Harcourt Arboretum - University of Oxford

8
Botanic Garden News | No. 79
Recent developments at the University of Oxford
Botanic Garden and Harcourt Arboretum
The fruits of Magnolia campbellii ssp
mollicomata have given a good show at the
Garden. These rather unpleasant looking
structures are a vivid cerise with erumpent
orange seeds. Each seed is housed in a
separate ovary which is easier to see at this
time of year than in the spring when the
plant is in flower. For the first time that I can
remember, the Magnolia x soulangeana has
also set fruit.
Magnolia campbellii ssp mollicomata
Back at the Garden the fruiting of the
woody plants has been matched by the
flowering not only on the Autumn Border
but also on the big Herbaceous Border. At
the beginning of September this was looking
as good as it has all year, perhaps benefiting
from the mild, wet summer. For many visitors
the highlight of the Autumn Border has been
not the dahlias but the salvias. In particular,
Salvia oxyphora, which is a pink that you
might think was incompatible with any
other colours and yet it looks wonderful with
Canna musifolia and Dahlia ‘Summer Night’.
Two plants have excelled this year at
producing scent in the evening. Whilst this
is an unhelpful comment when the Garden
closes at 5pm these are two plants which
Friends might like to have at home. The first
is Clerodendron trichotomum var. fargesii. We
grow this against a west facing wall and it is
very happy. The ivory coloured flowers are
presumably pollinated by moths. A tender
plant for a conservatory attached to the house
is Murraya paniculata the scent of which
is very similar to that of the Clerodendron
outside. We grow it in a shady part of the
Palm House. Whilst in this area it is worth
mentioning a new flowering record for the
Garden: for many years we have been nurturing
a plant of Cubanola domingensis from
the coffee family, the Rubiaceae. The flowers
are extraordinary – tubular and pale yellow,
they hang vertically downwards, and are
more than eight inches long. We do not know
yet what pollinates it but it is an amazing
example of the apparent extravagant, almost
wasteful, nature of biology.
1 Harris & Harris (2001) Plant Identification
Terminology. Spring Lake Publishing
(a must-have book for a gardener interested
in plant bits).
2 Campbell CS et al (2007) “Phylogeny of sub
tribe Pyrinae” Plant Systematics & Evolution,
Vol 266, pp119-145.
3 Robertson et al (1991) “A synopsis of genera
in the Maloidae (Rosaceae)” Systematic
Botany, Vol 16, pp376-394.
4 Potter D et al (2007) “Phylogeny and classification
of Rosaceae” Plant Systematics &
Evolution, Vol 266, pp5-43.
5 Bean WJ (1980) Trees and shrubs hardy in
the British Isles, Vol 4, pp399-404.
The herbaceous border at the Botanic Garden