All change on the Autumn Border

At this point in the year the Garden has normally wound down, growth having been halted by a sudden autumn frost. But not this year. With the unseasonably mild autumn plants, particularly the tender perennials, have been growing and flowering their socks off up until late November.


Last year we experienced a hard frost in early October, putting an abrupt and premature end to the display of Dahlias, Salvias, Cannas and annuals on the Autumn Border. In contrast, this year we have been eagerly awaiting the arrival of the first frost.

The plants made a fantastic display this year. Particular favourites were; Dahlia 'Dovegrove', Dahlia 'Moonfire', Salvia curviflora, Salvia oxyphora (left) and Canna 'Musifolia'.

Whilst colour plays a very important role here, so does form. As a foil to the floral extravagance we use plants such as Euphorbia x pasteurii, Cotinus 'Grace', Melianthus major and Clerodendron bungeii to add structure and contrast.  We also used Amicia zygomeris in this border for the first time this year to great effect.

The Garden is a dynamic place, but at the same time managed on a fairly rigorous schedule. This is necessary to  ensure seasonal interest and succession of flowering through the growing season. To this end, we had to bite the bullet last week and cut back all the Dahlias, Salvias & Cannas whilst still in full flower to make way for the tulips.

We revel in tulips at the Botanic Garden, planting around 3000 each year. Some we save once flowered, lift, store and replant if in good condition, others we replace to keep us, and the visitors, interested. So the tender perennials were removed, stored in crates filled with spent potting compost and tucked in to deep frames or cool glass for their winter hibernation. They will be stirred into life again next spring, potted on individually and then replanted in the Garden next summer.

This year we are plating the following varieties, most of which we know well but a few are new: 'Abu Hassan', 'Angelique', 'Apeledrorn', 'Ballerina', 'Bolroyal Honey', 'Cairo', 'China Pink', 'Don Quichotte', 'Ile de France', 'Inzell', 'National Velvet', 'Negrita', 'Oxford', 'Red Shine', 'Ronaldo', 'Spring Green', 'Westpoint', 'White Triumphator'. To the right is a picture of one section of the Autumn border form spring 2011 showing T. 'Ballerina' and T. 'Red Shine' together. A great combination, one that we will use again this year.

This picture shows another area of the same border,
planted with T. 'Westpoint' and T. 'Abu Hassan'.
This year we are mixing the red T. 'Oxford' in with the yellow T. 'Westpoint' for a bit more drama. 'Westpoint' can also fade early, so 'Oxford' along with the underplanting of Myosotis (forget-me-not) combine to prolong the interest in this planting.


Once the ground is cleared of the tender stuff, the soil is cultivated, firmed and then levelled. The Myosotis are planted at 30cm spacings and the tulips scattered in amongst at 10cm spacings, planted 10cm deep. This year we had the help of volunteers from the Friends of the Botanic Garden and Harcourt Arboretum assisting to complete the planting in two days. The display next April and May promises to be spectacular.

Sowing the seeds of success....

The University of Oxford Botanic Garden has undergone dramatic change over the past three years. A suite of developments including the new Medicinal Plant Collection and the Vegetable and fruit Collections, culminates with the sowing of the new Merton Borders.


These borders replace what was previously lawn area and cover an area of 955m2, the largest single cultivated area in the Garden.  The Botanic Garden has chosen to make these plantings an example of sustainable development and a celebration of plant diversity. All of this whilst minimising the impact on the environment, from plant establishment through to long-term management. As such these new borders will be established through the direct sowing of seed of over 100 different species.

The Garden is working in collaboration with James Hitchmough, Professor of Horticultural Ecology, the Landscape Architecture Department, University of Sheffield. James' research focuses on the creation of naturalistic herbaceous vegetation for use in urban parks and greenspace. These vegetation types are based on semi-natural plant communities but involve both native and exotic species to create visually dramatic, yet highly sustainable designed plantings that are managed mainly through the application of nature conservation techniques such as cutting and burning.

The new plantings at the Botanic Garden are based on seasonally dry grassland communities in three biogeographic regions of the world: the Central and Southern Plains of the USA, high altitude areas of Eastern South Africa and lastly, Southern Europe to Turkey and across Asia to Southern Siberia. Once established the area will be transformed into a sustainable, dry (non-irrigated), highly ornamental planting.




The aim is to showcase plants and planting that are likely to
become more important in the future if current climate change models prove to be accurate. The planting will be extremely innovative as it is based on the scientific study of the ecological rules governing natural plant communities. It will be an excellent example of the practical application of scientific research in British horticulture.  

James designed species lists for each biogeographical zone and calculated quantities required of each taxa to ensure a target of 70 plants per square metre. Seed mixes for the different areas were weighed out at the Department of Plant Sciences the day before sowing. The area was then marked out according to James' plan, breaking up the area into nine alternating zones of the three different plant communities. Containerised plants, that do not establish well from direct sowing, were then randomly placed through the scheme and planted.  


The seed batches were mixed with sawdust before hand sowing each area in turn. The sawdust acts as a carrier for the seed, and also allowed us to see which areas had been sown and if sowing had been conducted evenly. Two sowings were made across each area, at right angles to one another, to ensure even distribution of the seed 


The seed was then raked in by hand and jute netting laid over the entire area. This will keep the sand layer in place and prevent squirrels, cats and foxes digging the surface up.


Germination will occur in spring 2012, with the first flowering in late summer. Watch this space for updates!

The Oxford Rare Plant Group

August bank holiday monday morning was spent on Port Meadow surveying the population of the creeping marshwort, Apium repens. This is an endangered plant in Europe, and for a long time Port Meadow was the only recorded locality for this species in the UK. It is a member of the Apiaceae, the carrot family, and in September produces tiny white flowers.


It is, to an extent, a rather insignificant little thing growing on the heavily grazed flood plain to the north-west of Oxford. This area of common land, beside the River Thames, is an ancient area of grazed land seasonally inundated but otherwise home to cattle, horses and some interesting birdlife.


The creeping marshwort seems to enjoy the conditions here, where the grass sward is kept low by grazing. The population fluctuates year on year and is dicatated by the environmental conditions of the site. 

There are some concerns that the species is hybridising with another Apium found here, A. nodiflorum. Telling the two species apart is difficult enough, let alone the hybrid!


In the past the University of Oxford Botanic Garden has been involved with reintroduction programmes. The hope is to work on further reintroductions over the next few years. 


Check out this link for more info:
www.oxfordrareplants.org.uk