Thursday, November 18, 2010

Fancy a trip to Tenerife?

Tenerife. A cliched tourist destination loved by us sun-starved Brits, or a dramatic botanical island paradise? Perhaps it's a bit of both! Having returned from a week on the island at the beginning of November, I know which one I'd go for. The lasting impression is one of spectacular scenery crammed full of interesting plants.

The spread of high-rise hotels and apartments around the coastline is certainly alarming, however, as I discovered, there is another world beyond the swimming pools and ranks of sunloungers. For anyone with an interest in plants, Tenerife is a fantastic location and full of interest.

Commonly regarded as the most varied of the Canary Islands, Tenerife boasts an incredible array of climatic zones crammed into a small area, all thanks to the islands volcanic origins. The South of the island is classified as semi-desert, being hot and very dry. The annual mean temperature here is around the 18oC mark. Head inland and up into the mountains, and the conditions change, and so too does the vegetation, until the sub-alpine habitat of the hugely impressive volcanic calderea is reached. The Northern slopes of Tenerife can be much wetter than the South due to the North East trade winds bringing moisture in off the Atlantic. The Anaga Moutains in the far North West contain the most extensive region of sub-tropical cloud forest to be found in the Canary Islands.

During our visit, we were able to make trips to explore all these areas, and for me, it was an exciting time. Having the opportunity to see plants growing in the wild that I use in gardens here in the UK must surely be the best way of understanding their specific requirements. Inspiration for future projects was to be found around almost every corner.

And so to the photos! Rather than this becoming an excuse to show off my holiday snaps, I have focused on plant related shots that I hope will be of interest. Let me know what you think!

The Southern coastal strip, up to about 800m in altitude, is hot and dry for much of the year, and rain outside of the winter months is very rare . The plants here must tolerate heat and drought, and the flora has been likened to parts of the Sahara. Plant communities are dominated by various types of Euphorbia. Opuntias are extremeley common weeds, as is Agave americana. There are very few wild populations of Phoenix canariensis left in Tenerife, but we found this palm growing in Barranco de Masca, where there is ground water all year deep in the bottom of the gorge.


Opuntia ficus-indica in flower


From a UK gardeners perspective, you could be excused in thinking that there is little of interest here, afterall, desert plants such as these are not going to survive even a mild winter in the UK. However, I was struck by the visual effect created by these communities of plants. Why not create a garden that uses different species to create the same visual impact?





Large stands of Euphorbia canariesis growing in Barranco Seco

Euphorbia atropurpurea in flower

Groves of mature Phoenix canariensis growing at the head of the Masca gorge

The Anaga Mountains lie in the North West of Tenerife; an area of steep sided, razor ridged mountains cloaked in dense cloud forest. Almost every day of the year, the trade winds blow in off the Atlantic and bring moisture that produces mist and cloud as it is pushed over this high ground. The forest is made primarily of 4 species of evergreen Laurel, as well as giant 30 foot high tree heathers. Vegetation and moss appears to cling to every surface.

Ferns carpet the understory, particularly Woodwardia radicans. Aeonium cuneatum is common growing out of the dripping rock faces.



Typical cloud forest in the Anaga Mountains

Aeonium cuneatum was common on rocky areas in the cloud forest


Isoplexis canariensis



Asplenium Hemionitis, one of many fern species found

Higher up, between 1000m and 2000m, lies the pine forest zone. This beautiful area is dominated by the Canary endemic, Pinus canariensis. The pines themselves are an important coloniser of relatively recent lava flows. Other plants found as an understory are Cistus symphytifolius and Lotus campylocladus.

The upper reaches of the Pine Forest Zone

For most visitors, the sceneic highlight of Tenerife is the high volcanic caldera - the remains of a vast crater, now dominated by the bulk of Pico del Teide, at 3717m. The caldera floor is at an altitude of over 2000m, and being enclosed on all sides by sheer mountain walls, cold air sinks and collects as a giant frost pocket during the winter. It gets pretty chilly here. Frosts are common, and snow is not unusual; a record low of -16 has been recorded according to some sources, although this is exceptional. This is the home of Echium wildpretii, which in my eyes, is the most striking of the Echium species and I was keen to find it. I wasn't disappointed, as although we were too late to see it in flower, the remains of it's flower spikes were easily spotted, glowing as they caught the sunlight.



Echium wildpretii with Pico del Teide in the background


Echium wildpretii is considered marginal at best in the UK, and I have only achieved flowering when overwintering it in a frostfree greenhouse. Nearly all those that we saw in the caldera were growing out from under a stone or boulder, presumably gaining protection and shelter from the worst of the cold. I could be tempted to try E.wildpretii again and growing it under similar conditions in a south facing, well drained, sunny position.

As I write this, Tenerife seems a distant memory. With new records for early season cold and snow being set left, right and centre in the UK, the temptation for booking a 2nd visit is growing stronger each day!