Christmas
Advent Botany 2016 – Day 25: Erica x darleyensis — Culham Research Group
It seems only right to devote the Christmas Day blog for Advent Botany to a plant that has brightened my winter garden for many years, Erica x darleyensis. This hybrid heath was first reported from a nursery in Darley Dale, Derbyshire in the late 1800s. It is a hybrid between the smaller winter heath, Erica…
via Advent Botany 2016 – Day 25: Erica x darleyensis — Culham Research Group
Advent Botany 2016 – Day 24: Professor Vernon Heywood — Culham Research Group
By DrM Vernon and Christine Heywood (photo: Stephen Jury) Dr M introduced to #adventbotany this year, #adventbotanists, botanists whose birthdays fall within advent. The first featured Erasmus Darwin a great botanical mind from a bygone age. Dr M’s second #adventbotanist features Vernon Heywood, born on 24th December 1927, widely recognised as a world authority on…
via Advent Botany 2016 – Day 24: Professor Vernon Heywood — Culham Research Group
#Advent Botany Day 23: Vanilla – nothing plain about this flavour!
I’m not one for cream on my Christmas pudding, it just has to be custard or ice cream and so what I’m really admitting to is a love for vanilla. Vanilla is the quietest spice at Christmas but there is so much more to vanilla than merely two scoops of icecream.
Natural vanilla is the fruit and seeds from a tropical, climbing orchid. There are other edible orchids (e.g. Dendrobium flowers and salep tubers), but it is certainly the most commonly used in food preparation. Some orchids are harvested from the wild to eat (such as Orchis mascula and O. militaris for salep), but given the demand, luckily this isn’t true for vanilla. There are over 100 orchid species in the Vanilla genus, but the most commonly cultivated species is Vanilla planifolia (more commonly known as Madagascan or Bourbon vanilla).
V. planifolia is native to Central and South America, and was first domesticated by the Totonac people of east Mexico, who used it exclusively until Aztec conquerors demanded vanilla as a tribute. The Spanish conquistador Cortez brought vanilla to Europe, where initially it was only mixed with cocoa and drunk, but later was used in other deserts. Vanilla was very expensive during the 16th to 19th century, as Mexico had a monopoly on this luxurious spice. The reason for this was discovered by the French botanist Charles Morren who in 1836 observed Melipona bees pollinating the flowers, which have a range limited to Mexico. Therefore, the only way to cultivate vanilla elsewhere is by hand pollination. Morren experimented with hand pollination methods but the method still used today was devised by Edmond Albius, aged 12, in 1841. A twig or blade of grass is used to lift the rostellum, separating the stigma and anthers, and the thumb is used to transfer pollen to the stigma. The process is further complicated by each infloresence only lasting for 24 hours.
Vanilla is labour intensive to produce, so natural vanilla is still the second most expensive spice (after saffron). Albius’ method allowed vanilla to be grown in what is now Madagascar, Reunion and the Comoros Islands, which today account for 80% of the world’s vanilla pod production. You can find more about vanilla from the National Geographic website and an interesting site dedicated to vanilla.
For centuries vanilla has been used to flavour our foods, drinks and even pharmaceuticals but the main extract from the vanilla pod, vanillin, wasn’t isolated until 1858. Nicolas- Theordore Gobley obtained it by completely evaporating the vanilla extract and then recrystallizing it from hot water in order to separate it out from all of the several hundred other components found in the extract. Since the 1870’s companies have competed to produce synthetic vanillin from clove oil, lignin, guaiacol and glyoxylic acid. More recently, Rhodia has marketed a “natural” vanillin which is prepared using microorganisms. You can find out more about the structure of vanillin here.
Around 2% of the dry weight of the cured pods of Vanilla planifolia is vanillin. When the seed pods are first harvested, they are green and lack the vanilla flavour and aroma. Curing of the vanilla pods consists of just four steps. “Killing” often entails the pods being frozen or blanched in hot water to initiate reactions which develop the aroma. Sweating involves stacking pods within layers of wool for 7-10 days in a very hot (45–65 °C) and humid environment. Drying occurs to reduce the remaining moisture content to around 25% in order to prevent rotting. Conditioning is the final step where the pods are left in the box for several months before being graded. It is after this curing process that vanillin develops the aroma and flavour that we have come to know and love.
To get into the Christmas spirit I’ve found some very Christmassy treats for you to make at home yourself:
A tropical Christmas pudding with a vanilla glaze and beautiful danish cookies (vaniliekager) recipe.
Advent Botany 2016 – Day 20: Virgin birth and hidden treasures: unwrapping some Christmas figs — Culham Research Group
By Katherine Preston & Jeanne Osnas Figs reach their peak in summertime, growing fat enough to split their skins under the hot sun. It’s nearly impossible to keep up with a bountiful tree, and many a neglected fig is extravagantly abandoned to the beetles. Beetles gorge on a fig@BitKblog But here we are, halfway around…
Advent Botany 2016 – Day 19: Christmas Gourds — Culham Research Group
By Dawn Bazely Prince Albert, the father of the Victorian Christmas Prince Albert, who moved to England from Germany, to marry the young Queen Victoria, led the Victorians in inventing much of today’s Christmas aesthetic that dominates Britain and North America. But, the Nativity is celebrated by diverse cultures throughout the world, and is much…
via Advent Botany 2016 – Day 19: Christmas Gourds — Culham Research Group
Advent Botany 2016 – Day 18: The Madonna Lily — Culham Research Group
By Robbie Blackhall-Miles Mary and the Lily http://allaboutmary.tumblr.com Not realising the hope they give me, through their winter rosettes of green, the bulbs of the Madonna lily (Lilium candidum) sit snugly in the soil year on year producing an ever-widening clump. Naturalised across Europe, and finding a happy home in the gardens of the UK,…
via Advent Botany 2016 – Day 18: The Madonna Lily — Culham Research Group
Advent Botany 2016 – Day 16: Raphia: a string for all seasons — Culham Research Group
By Yvette Harvey RHS Garden Wisley, Woking, Surrey, GU23 6QB Raffia hat Forget the gorgeous Madagascan bags, the baskets, the hats, the dates, the coconuts, the wine, the patterned mats and shoes, the most important product made from a palm has to be the string that holds the wrapping paper in place for your Christmas…
via Advent Botany 2016 – Day 16: Raphia: a string for all seasons — Culham Research Group
Advent Botany 2016 – Day 14 – Caraway — Culham Research Group
By Emma (the unconventional gardener) Cooper Caraway, Carum carvi It’s possible to grow up in the UK and never consciously encounter caraway as a spice – I certainly did. And yet this versatile plant adds flavour to meat, fish, and vegetables details. But it’s claim to Christmas fame comes from its ability to make stand-out…
via Advent Botany 2016 – Day 14 – Caraway — Culham Research Group
The Poison Chronicles Festive edition: Poisoner and matchmaker – the joys of mistletoe
Guest blog by: Laura Cooper

Whilst many species of plants are referred to as mistletoe, the icon of Christmas is the European Mistletoe Viscum album. Mistletoe has a varied reputation; it is a symbol of Christmas and druidic ritual, a poisoner and a matchmaker.
The plant itself belongs to the Santalacea or sandalwood family. It is found throughout much of Europe, but in the UK is localized to the central south. V. album lacks its own trunk and instead grows in the crowns of host trees including apple, lime, hawthorn and poplar when its seeds are dispersed by birds smearing the sticky fruit and seed from their beaks onto the bark of the host. V. album is not a true parasite but a hemiparasite. This is because whilst the seedling sends its haustorium from the roots through the bark of the host to induce the host’s xylem vessels to supply it with water and nutrients, V. album makes its own sugars through photosynthesis. A heavy infestation of mistletoe can take over the entire crown of a tree preventing the host photosynthesising and building its own tissue which can lead to the death of the host.
V. album owes its toxicity to large amounts of the alkaloid tyramine throughout the plant, which is also present at lower levels in foods including cheese. As with most toxins, it is the dose that makes the poison, not the chemical. Whilst little research has been done on the effects of consuming V. album, it has been reported that consuming enough of the leaves or berries can result in nausea, abdominal pain, diarrhea and death. However, the well-known risks of mistletoe means poisoning cases are very rare. As the Poison Garden argues, artificial mistletoe is likely more dangerous as a choking hazard to children than live mistletoe is as a poison.

Whilst mistletoe is commonly linked with druids, the only account of a druid ceremony involving mistletoe comes from Pliny the Elder. He details a banquet and ritual sacrifice where a druid would climb an oak tree, cut the mistletoe with a golden sickle and drop it into a cloak to prevent it touching the ground and losing its power. The link between druids and mistletoe was picked up in the revival of druidry in the 18th century and today druids carry out a similar ceremony, without the human sacrifice! The tradition of kissing under the mistletoe at Christmas is not a Christian tradition but also derives from the association of mistletoe with fertility in druidic mythology. Christianity has a less favorable relationship with mistletoe, as according to tradition mistletoe wood was used to makes Christ’s cross and ever since could not grow upon the earth so was condemned to parasitic life.
Mistletoe has also been used as a medicine historically, including as an epilepsy treatment. Today, injection of extracts of mistletoe has been used as an anti-cancer treatment in alternative and complementary healthcare. Whilst it has been shown to kill cancer cells, the few trials done were inconclusive or poorly done, and the NHS advises that there is currently no reliable evidence that mistletoe is effective at treating cancer.
For more mistletoe information, see: