"Enhancing the Discovery, Understanding and Appreciation of Nature since 1621"
Tuesday, 22 January 2013
Sisal and Snowdrops
Agave sisalina plantation in Java (Tropenmuseum of KIT, NL)
Our Agave sisalina has become a media star. At the weekend the Oxford Mail produced a short article entitled, 'Garden's Rare Cactus Shrugs Off the Snow'. Protected from the elements in the Arid House, the Agave is flowering for the first, and last time. Agave plants are monocarpic- once they have flowered they die. As you might expect, this once-in-a-lifetime gesture is a dramatic one. The inflorescence spike, or 'mast', can grow to six metres and resembles a giant asparagus spear. This provides a clue to its true identity for, despite an association with arid areas, Agave is not a cactus. It is a member of the large Asparagaceae family and numbers Chlorophytum (the Spider Plant), Yucca and Hosta among its closest relations. Fortunately this Agave, grown commercially for sisal fibre, is not rare. Brazil alone produces over 100,000 tonnes of sisal fibre every year. The inflorescence spike has already achieved an impressive size and may not have enough room to flower, but it already makes one of the more unusual floral displays on offer in wintry Oxford.
Agave sisalina plantation in Oxford
Outside, rare plants are shrugging off the snow. Snowdrops of many different kinds are appearing in different parts of the garden and in the following weeks will be joined by other early flowering spring bulbs such as Eranthis and Narcissus. The most well-known snowdrops are from the species Galanthusnivalis which is native to many parts of Europe but, surprisingly, not to the British Isles. It may have been introduced as late as the 16th Century and 'wild' populations are, in fact, naturalised. In Europe a combination of habitat loss and over-collecting for trade has led to a declining wild population. In Bulgaria it has Critically Endangered status.
Cultivated snowdrops, which are propagated and sold without threatening wild populations, come in over 500 varieties. Some of these can be seen at the Botanic Garden providing a subtle and rather more familiar contrast to the giant in the Arid House.