The resilient plants of the western Mediterranean

By Helen Roberts

A recent talk to the Friends by Dr Chris Thorogood on the flora of the western Mediterranean was tonic for those of us longing for warmer weather. For Chris, the western Mediterranean has always had great appeal having spent many summers teaching field courses to undergraduate students at the University of Bristol and the last five years conducting fieldwork for his new book, a field guide to the area.

“The flora of the Western Mediterranean is really special. The plants are able to grow in some fascinating but really harsh places,” explains Chris. “Because of these severe conditions, plants have evolved numerous coping mechanisms in order to survive.”

The region is extremely rich botanically, with over 10,000 different species, all of which are specially adapted to particularly taxing conditions. The area covers a huge geographical expanse incorporating the westerly Portuguese Algarve, to Italy in the east, the islands (Balearic Islands, Corsica and Sardinia) and North Africa from Morocco to Tunisia (see my post last week, which discusses these regions in more detail).

A bounty of habitats: scrubby landscapes

There is a diverse range of floral habitats in the region from the scrubby maquis to forests with wonderful understories of orchids. The bare and arid habitats are home to ‘experts’ in drought tolerance; and at the other end of the watery spectrum are the seasonal lakes where deadly predatory plants reside. Humans have shaped the flora as well through thousands of years of agriculture, which has produced a visually evocative landscape throughout the whole Mediterranean basin.

Cistus ladanifer, the common gum cistus.
Photo credit: Henry Bush [via Flickr, CC]

A habitat that we so often associate with the Mediterranean landscape is maquis, which is specific to the Mediterranean area. It is comprised of spiny sclerophyllous  (a fancy word for hard-leafed) tough vegetation, which is specially adapted to cope with severe drought. There are often small trees and shrubs dotted about, often with beautiful understories of bulbs and short-lived annuals. Many of the species are aromatic. Typical species include prickly juniper (Juniperus oxycedrus) and common gum cistus (Cistus ladanifer), both highly pungent plants that are used by the cosmetic industry for their oils.

“The smells that exude from maquis vegetation are wonderful,” exclaims Chris, “and the scent from these aromatic plants just seems to hang on your clothes long afterwards.”

Garrigue vegetation is similar to that of maquis. It differs slightly in that it is low growing in form, occurs closer to the coasts and grows on shallower soils. Due to its close proximity to the coast it is battered by winter storms and winds. The low stature of the garrigue evergreen scrub means that perennials and bulbs are highly visible. The flowering displays in spring are visually spectacular and include wild tulips, crocuses, thymes, mints, helichrysums and lavenders.

Into the woods

The native forests of the western Mediterranean form prominent landscapes occupying quite different terrain than the shrubland regions. The oak woodlands are dominated by the holm and cork oak, with a spectacular understory that offers a refuge for many animals, including the endangered Iberian lynx.

The pine forests of Pinus halepensis and Pinus pinaster occupy coasts and cliffs. Healthy habitats have a particularly distinctive flora and fauna with rarities such as the semi-parasitic Violet Limadore orchid found in the maritime pine forest of Landes in France.

Ceratonia siliqua, commonly known as the carob tree.
Photo credit: Jesus Cabrera [via Flickr, CC]  

Humans have also shaped the forest landscapes of the region to a certain degree. Traditional farming practices in the Mediterranean have created unique assemblages of plants. Olive, carob, fig and almond groves represent landscapes people often associate with the Mediterranean. No other landscape denotes the true essence of the Mediterranean like a grove of olives. The olive is engrained in the lives and culture of the people of the region. Carob groves are also stunning in their composition with the gnarly dark trunks contrasting brilliantly against the green understory. The carob, Ceratonia siliqua, is a member of the ‘peas’ (Fabaceae), the most speciose family in the Mediterranean.

Rare aquatic habitats

Most of the western Mediterranean habitats are dry and parched, but surprisingly there are some wet ecosystems too. These unusual habitats are rare and include some curious species like the carnivorous bladderworts, found in seasonal lakes, which catch insect prey using sticky hairs and trap doors.

“The aquatic habitats of the western Mediterranean are interesting because they are pretty rare,” explained Chris. “Many are only seasonal but they support a wealth of interesting species from tiny forget-me-nots, tongue orchids and the carnivorous bladderworts.”

Tough but not invincible

While the native species of the western Mediterranean might be seen as tough and indestructible in the harsh landscapes they occupy, they are extremely susceptible to invasive alien species (IAS). Chris explained that the two most invasive plants in the region include certain species of Eucalyptus and Acacia. People assume these species are native, probably because they fit into the landscape visually and they can tolerate harsh climatic conditions. However, both these trees can alter native ecosystems and have a negative impact on biodiversity. Unfortunately, many are still planted as ornamental shrubs despite measures drawn up to prohibit the cultivation of them.

Chris explains the danger of one such exotic: “Acacia cyclops is an invasive species that is likely to become the next big invasive in the western Mediterranean. This species forms a mass of vegetation in barren landscapes due to its ability to cope with extremely dry and saline conditions. Ultimately it outcompetes native species.”

These invasive pests steal native plants’ water and change the biochemistry and microbiology of the soil. The native flora is sensitive because the western Mediterranean is exceptionally biodiverse in a relatively small area, with high levels of endemism, particularly on some of the islands. As well as the threat from IAS, there is also intense pressures on these fragile native habitats from humans due to urbanisation, afforestation, and coastal and agricultural development. Effective and timely conservation measures are vital to ensure the survival of these beautiful and botanically rich habitats before it is too late and they go into decline.

Helen Roberts is a trained landscape architect with a background in plant sciences. She is a probationary member of the Garden Media Guild and a regular contributor to the University of Bristol Botanic Garden blog.

Floral visits to the western Mediterranean

By Helen Roberts

A floral excursion to the western Mediterranean at this time of year appeals to many of us. The anticipation of warm weather, beautiful landscapes and a dizzyingly diverse range of exquisite wild flowers and I want to pack my bags in a flash. I certainly felt that way when I saw some of the images of the region’s wild flowers in a recent Friends‘ talk given by botanist Dr Chris Thorogood.
However, if you cannot escape overseas, then the Mediterranean collection at the University of Bristol Botanic Garden will give you a taste of some of the Mediterranean Basin species although you will have to wait till later in the year to see some of the flowers in bloom. 
If you do have a trip in mind though, here are a few of Chris Thorogood’s favourite spots to see the wild flowers of the western Mediterranean:
Cape St Vincent, Portugal. Photo courtesy of Peter Broster via
Flickr [CC license]

The Algarve, Portugal:

This area has a diverse flora due to varied geology and weather with numerous endemic species and beautiful wild flower meadows. Cape St Vincent, the most south-westerly point in the area and a vast nature reserve, has a spectacular display of flowers in the spring and early summer (January through to the end of May). There are many unique species of thyme and endemic rarities like the tiny diamond flower (Ionopsidium acaule).

Almeria, Spain:

This province is located in the southeast of the Iberian Peninsula and has a wealth of species adapted to cope with extremely dry conditions. Many plants are salt tolerant including sea lavenders like Limoniuminsigne and the rare low growing lily, Androcymbium europaeum whose flowers emerge on sand dunes in mid winter. An area called Cabo de Gata, an impressive tract of volcanic cliffs, is host to numerous unusual species. Many of these are freakishly odd looking from the succulent Caralluma europaea with its purple and yellow striped flowers to the phallic form of the parasitic Cynomorium coccineum.

Cap de Formentor, Mallorca:

This peninsula in the northeast of the island has many unique sea lavenders and orchids. Endemics are closely dotted only metres apart. Much of the landscape is fairly inaccessible due to its rocky and precipitous nature so one needs to be fairly adventurous to spot some species. Notable endemic species include Arum pictum, an arum that smells of rotten meat to attract its fly pollinators and a species of St John’s Wort unique to Mallorca, Hypericum balearicum.

Maremma, Southern Tuscany, Italy:

The Maremma region is rich in wild flowers and contains 25% of all Italian flora. It has a unique geology and extremely varied landscapes including the protected coast, swathes of pine forest and abandoned agricultural plains. The giant fennel, Ferula communis, is one such distinctive plant with its towering inflorescences that can take many years to develop.

Gargano National Park, Puglia, Italy:

The yellow bee orchid (Ophrys lutea) is one of the orchid
species found in Gargano National Park.
Photo credit: Alastair Rae [via Flickr, CC license]
This park has a unique flora and are highly specialised for growing in certain conditions many being endemic. The park covers a vast area and as a result the landscapes are varied from rich beech forests, steep cliffs, karstic plateaus and scrubby maquis. There are many orchid species here (over 65) including some unique bee orchids.

Helen Roberts is a trained landscape architect with a background in plant sciences. She is a probationary member of the Garden Media Guild and a regular contributor to the University of Bristol Botanic Garden blog.

A Sicilian Grand Tour

By Helen Roberts

It was a distinctly overcast, grey, cold and rainy day last November in Bristol when I went to see Nick Wray, curator of the University of Bristol Botanic Garden, give a talk. I, like most people, was definitely feeling the lack of sunshine, but Nick’s talk on Sicilian landscapes certainly helped blow away the winter blues and had me looking forward to (hopefully) another blistering summer.

The Botanic Garden’s interest in Sicily 

Medieval farm quad at the Tasca d’Almerta in the
central rural mountains of Sicily

Nick has been working with a Sicilian horticulture colleague, Sergio Cumitini, for the last 5 years to establish a joint acclimatization project. The project has involved growing Mediterranean plants in the UK at various sites including Bristol’s Botanic Garden, RHS gardens and Tresco Abbey Garden on the Isles of Scilly. It was through this work that Nick became fascinated with the plants and landscapes of Sicily. His fascination led to a plant and garden tour to the island in spring 2013, which involved an introduction to the gardens, architecture and landscapes of the region as well as some visits to beautiful private gardens. For those who couldn’t go on the tour of Sicily, Nick’s November talk brought the Sicily tour to Bristol.  
Nick talked extensively about the flora of Sicily, both native and cultivated, and showed how the cultures and landscapes of the island are markedly connected. He toured us around a number of important buildings and landscapes starting in Sicily’s capital Palermo fanning out from the city and then around the island itself.

The native flora

Sicily is very rich agriculturally due to both the climate and the nutrient rich ash deposited from volcanic eruptions. The flora is distinctive and classed horticulturally as ‘maquis’ or ‘macchia’ in Italian, which refers to this Mediterranean biome that is rich in evergreen shrubs and deep rooted perennials. These plants are adapted to cool wet winters and blistering hot summers.
The vegetation can change with altitude and near Mt Etna – one of the world’s most active volcanoes located on the east coast of the island – the flora is distinctly temperate, whereas in parts of Palermo it can verge on sub tropical.
Also within the Sicilian landscapes are beautiful meadows filled with deep-rooted perennial herbs and aromatic shrubs, such as the spicy smelling curry plant, licorice scented fennel and pungent Tree Wormwood.

Cultures and landscapes inextricably entwined

The first major cultural impact on Sicily was by the Greeks, who built major colonies, such as Agrigento, between the 8th and 6th centuries BC. The people prospered here due to the rich alluvial plains, ideal for growing cereals, fruit and vegetables. The Greeks also introduced olives and vines to Sicily.

In the 3rd century BC, the island became the first Roman province and was held by the Roman Empire for over 6 centuries. Sicily was important in providing food for Romans and was termed ‘Rome’s bread basket’. The Byzantines occupied Sicily in AD 535 until 965.
In 965 the island fell to Arab conquest from North Africa. The beginnings of Arab invasion occurred in 827 (and lasted until 1091) and they successively conquered the major settlements. Palermo became the capital and grew into one of the most populous and cosmopolitan centres of the world with Hebrew, Latin, Greek and Arabic being spoken. Trade flourished, largely due to the island’s central location in the Mediterranean; Sicily has been at the crossroads of trade for over 8000 years. As a result of this trading hotspot many plants were introduced to Europe over thousands of years.
The Arabs worked wonders in agriculture, dividing large estates and diversifying production. They developed sophisticated irrigation systems, known as ‘qanats’, to provide water throughout the city, but these systems were then adapted to use in olive groves. The Arabs also introduced one of Sicily’s most important crops – citrus fruit.
Culturally, Arab gardens were heavily influenced by water and water features were important in symbolizing paradise. Water was often brought into the house by a series of rills, which in turn helped to cool the air inside.

Ancient cloister garden at the cathedral town of Monreale

From 1060 the Normans progressively settled the island and rather than destroying Arabic culture, they embraced it. The Normans were greatly impressed by Arabic architecture and continued to use Arabic architects and craftsmen in their buildings, such as San Giovanni degli Eremiti (a church in Palermo), the Cathedral of Monreale, and the Zisa (a castle in Palermo built for King William I of Sicily). All of these buildings have strong Arabic influences with decorative art on the walls and floors, and domes mounted on cubic towers.

In and around Palermo…


The Botanic Gardens of Palermo

False kapok tree (Ceiba speciosa) growing at the Palermo
Botanic Garden

Palermo Botanic Garden was founded in 1779 and was originally developed to grow medicinal plants. It has fantastic specimen plants including a number of Cycad species (given by the aristocracy of Naples to the aristocracy of Sicily), the beautiful False Kapok Tree, a number of different palms and cacti and the impressive Moreton Bay Fig (Ficus macrophylla). This latter beast of a tree has buttress roots that extend over an area of around 1,000 square metres (about 10,764 ft2). This aggressive tree starts as an epiphyte and then slowly strangles its host.

A British home in Sicily

There are many large country houses in and around Palermo. One of the more interesting is the Villa Malfitiano, an Italian mansion which was built by the Whittaker family (originally from Yorkshire) who made their money importing Marsala wine into Liverpool. This house has amazing examples of Trompe-l’œil with images of gardens painted on the walls. The gardens themselves have rare collections of trees.

Further out of Palermo

As you move out of the city, the built landscape gives way to small scale farming with groves of almonds and olives growing on the slopes. Here you can find weird and wonderful plants, many dependent on wild fire to colonise. One such odd looking poisonous plant is the mandrake (genus Mandragora), which belongs to the nightshades (Solanaceae) family. This genus flowers in October, but otherwise doesn’t look like much for the rest of the year.  Its root is believed to resemble a man and according to folklore, will shriek when pulled up (a fact that JK Rowling incorporated into Harry Potter). It is thought this is likely a rumour spread by herbalists as the plant has hallucinogenic and narcotic properties and they wanted to protect it!

A family estate

The privately owned estate belonging to the Marchesi Paternò Castello Di San Giuliano lies between Catalina and Syracuse and has been with the family for 800 years. The 4 hectare garden here has been developed over the last 40 years and has been gardened by British head gardener, Rachel Lamb, since 2002. It is truly Mediterranean in its use of plantings and also its aesthetics, with swathes of palms, eucalypts, bougainvillea’s, yuccas and succulents. There are beautiful stone pines and pergolas to provide shade and rills to provide irrigation. On the estate citrus are grown to make jams and marmalades, which are then sold at exclusive shops such as Fortnum and Mason.

The garden that wasn’t

Just south of Catania are the gardens of Villa Borghese, which were created by Princess Maria Carla Borghese from a former dry lakes side, a process that has taken forty years. The lake was a breeding ground for mosquitoes carrying malaria so in the 1930s the lake was drained. The fishermen left, leaving an ancient harbour wall that was built by the ancient Greeks; this wall is now in the heart of the garden and surrounded by immense succulents and palms.

An artist’s garden

In 1905, Casa Cuseni in Taormina, on the east coast of the island, was built by Robert Kitson, a famous English artist. In it’s heyday it had many famous visitors notably Oscar Wilde and Picasso. The terraced gardens were carefully designed to enhance the amazing views and are richly planted with citrus, roses, vines, wisteria and irises.

 A rich landscape tapestry

Sicily has it all, magnificent buildings, exceptional history, extreme geography and geology and exquisite landscapes and gardens. The sheer diversity of gardens and landscapes of Sicily is an indication of the many influences from different cultures over thousands of years on this truly distinct island. And if we don’t come by a sun drenched summer this year in England then you can always plan a trip to Sicily instead.

Nick will be leading a garden and landscape tour of Sicily again this year, from 26th April to 6th May. Click here for more information.