Tuesday, October 24, 2017

Plants vs. Winter: The Origins of English Conservatories

by K.M. Pohlkamp

Your ruthless Viscount patron has commissioned a heinous new poison. Your stores of toxic cuttings and seeds are running low and the backyard garden is blanketed with snow. Dear assassin, how will you grow the plant ingredients you need?

This dilemma developed while writing my historical novel, Apricots and Wolfsbane, set in the early 1500’s England. Yes, my assassin could have simply harvested a sufficient supply of seeds and cuttings during the previous fall. Yawn. She could have purchased supplies from a shadowy figure in the alley. Instead, I had her bartered for access to a solarium.

Since my character exists in early Tudor England, like a good historical fiction author, I began research period solariums only to find the word didn’t exist until about the mid 1800’s.

Well then.

A quick find and replace later, my assassin’s solarium transformed into a greenhouse.

Problem solved, right?

After all, greenhouse technology was first used in about 30 A.D. to provide the Roman emperor Tiberius with an ample supply of “cucumbers” which physicians believed would ward off his ailments. (Historical note: he likely did not eat cucumbers, but rather melons that lacked sweetness.)

The Roman philosopher, Pliny the Elder, described those first Roman greenhouses as:
“beds mounted on wheels which they moved out into the sun and then on wintry days withdrew under the cover of frames glazed with transparent stone.” 
 The “transparent stone” roofs were thin sheets of mica that were kept warm by maintained fires outside of the stone walls.

It wasn’t until the 13th century that the Italians built the first modern greenhouses (Giardini botanici) which fostered new species brought home by explorers of Africa, the Middle East, Asia and, later, the New World. Development of the concept spread and by 1450, Korea also had “temperature controlled” houses as documented by Jeon Son in his 1459 cookbook, Sanga Yorok.

These early structures comprised of modest wood or metal frames with glass. In southern Europe, a simple roof or a wall of windows maintained sufficient warmth thanks to the “greenhouse effect.” During the day, sunlight warmed the interior of the structure and the glass trapped enough residual heat to keep the plants content throughout the night, even in winter.

This was all great if my assassin was Italian, or Korean, or Spanish. But she’s English. Those early, simple concepts of passive heating proved insufficient against the harsh winter of Northern Europe. 

Thankfully for her (and me), the concept of greenhouses finally took root in England in the 16th century. But even before that time, the value of moving plants inside during cold nights was well understood by the English.

The Gardener's Labyrinth, written by Thomas Hill in 1577 under the pseudonym Didymus Mountain, was the first common gardening book written in English. The book describes the concept of a greenhouse by referencing Tiberius’ original inspiration: (You can download the beautiful original document here.)
“The young plants may be defended from cold and boisterous windes, yea, frosts, the cold aire, and hot Sunne, if Glasses made for the onely purpose, be set over them, which on such wise bestowed on the beds, yeelded in a manner to Tiberius Caesar, Cumbers all year, in which he took great delight . . .”
In the 17th century, glasshouses in Britain came to be called “orangeries,” developed to shelter citrus imported from Spain. Orangeries were originally built as extensions to large buildings but evolved to be separate structures. To fight the brutal winter, early English orangeries featured a charcoal underfloor heating system that dispersed warmth through channels called “hypocausts.” The structures had solid roofs and walls, usually with a large door to facilitate relocation of the trees. Maintenance of the greenhouses required attentive care to close at night and prepare for winter weather.

The popularity of orangeries grew in 1689 when William III took the crown of England, Ireland and Scotland. Also around this time in 1661, Louis XIV commissioned a great glasshouse for Versailles measuring 150 m (490 ft) long, 13 m (43 ft) wide, and 14 m (46 ft) high. These events further transformed glasshouses from university, government and scientific institutions into symbols of aristocracy and the social elite. In England, this status was especially bolstered by the 1696 “window tax” and the 1764 “glass tax.” 

The great English conservatories were born.

The word “conservatory” is derived from the Latin conservato (meaning “stored or preserved”) and the Latin root ory  (meaning “a place for”). However, the word came to invoke glazed structures for conserving or protecting plants from cold weather.

John Nash designed four conservatories for Buckingham Palace in 1825. However, when William IV ordered remodeling of the palace, one of the conservatories was moved to Kew in 1836. The structure remains the oldest, fully glazed greenhouse still standing. The design features structural columns to support the heavy weight of the glass panel roof and walls.

Nash House at Kew Gardens. Photo from Reference [3].

As symbols of prestige, glasshouses became cutting edge with increasing innovations. The magnificent glass and iron greenhouse of the Palm House in Kew was constructed under Queen Victoria between 1844 and 1848 by architect Decimus Burton and iron worker Richard Turner. To achieve construction on the massive scale, architects borrowed techniques from the shipbuilding industry, which provides rationale for why the building resembles an overturned hull. The structure consists of wrought iron arches held together by horizontal tubular structures containing long pressed cables. The center of the greenhouse nave is 19 m (62 ft) high.

Palm House Green House. Photo from www.kew.org

Sir Joseph Paxton, the gardens superintendent for the Duke of Devonshire, supervised the construction of an iron-framed Great Conservatory at Chatsworth house between 1836 and 1841. The conservatory covered three-quarters of an acre, and at the time, was the largest glass building in the world. Shaped like a tent, it measured 20.5 meters (67 ft) high and 84 m (277 ft) long. Eight boilers heated the conservatory, requiring the operation of ten men and seven miles of iron pipe. During the Great War, the massive amounts of coal required became unavailable, but all the gardeners were enlisted anyway.  Unattended, all the contained plants perished and the Great Conservatory was demolished in 1920.

However, the Great Conservatory became Paxton’s model for the Crystal Palace. Constructed in 22 weeks, the Crystal Palace covered 19 acres and was the largest enclosed space at the time. Containing 293,625 panes of glass, the palace spread five times as long as the Palm House (undoubtedly on purpose), and higher than Westminster Abbey. For his efforts, Paxton was knighted by Queen Victoria. 

The Crystal Palace. Photo from the BBC Hulton Picture Library.

The Crystal Palace was destroyed by fire on the night of November 30, 1936. The two surviving towers were demolished in 1941. The Walt Disney World Magic Kingdom restaurant of the same name was not modeled after the Crystal Palace in London, as you might expect, but rather by after the San Francisco’s conservatory of Flowers.

As all fads, the greenhouse craze would not last. Britain’s expanding empire and new wealth from the Industrial Revolution enabled the construction of an increasing number of glasshouses. However, the Industrial Revolution also decreased the cost of making glass so severely that the glass and window taxes were abolished in 1845 and 1851, respectively. Glasshouses subsequently became affordable to the English middle class and businessmen quickly realized that caste represented a larger consumer base potential. By the early 20th century, plain, self-assembled, small glasshouses were manufactured with iron structures for the common home garden.  

After hours of research, I determined it is possible my English assassin could have had access to a rudimentary glasshouse - if her connections possessed sufficient wealth. Such structures were not common in early Tudor England, but the concepts and technology were understood. However my research posed a new dilemma only I could answer: would access to such a luxury allow my ambitious assassin to prevail . . .


[1] Bruno, Gwen. “A Short History of the Greenhouse.” Dave’s Garden. March 1, 2012. Accessed July 13, 2017. http://davesgarden.com/guides/articles/view/3607#

[2] “History of the Conservatory” Richmond Oak Conservatories Ltd. Accessed July 15, 2017. http://www.oakconservatories.co.uk/history-of-the-conservatory/

[3] Hodgson, Larry. “A Brief History of the Greenhouse.” Laidback Gardener. January 27, 2016. Accessed July 12, 2017. https://laidbackgardener.wordpress.com/2016/01/27/a-brief-history-of-the-greenhouse/

[4[ Mountain, Didymus. The Gardener's Labyrinth. 1577.

[5] Paris, H.S. et al. “What the Roman emperor Tiberius grew in  his greenhouses.”  Cucurbitaceae 2008, Proceedings of the IXth EUCARPIA meeting on genetics and breeding of Cucurbitaceae (Pitrat M, ed), INRA, Avignon (France), May 21-24th, 2008. 

[6] “The Crystal Palace.” Disney Vacation Planner. Accessed July 16, 2017. http://www.solarius.com/dvp/wdw/crystal-palace.htm

[7] “The First Greenhouses: From Rome, to America.” RIMOL Greenhouse Systems Blog. February 4, 2013. Accessed July 14, 2017. https://www.rimolgreenhouses.com/blog/the-first-greenhouses-from-rome-to-america

[8] “Way Back When: A history of the English Glasshouse” Hartley Magazine. September 3, 2015. Accessed July 13, 2017. https://hartley-botanic.co.uk/magazine/a-history-of-the-english-glasshouse/


K.M. Pohlkamp is the author of the Tudor-era novel, Apricots and Wolfsbane, following the career of a female poison assassin. She is a proud mother of two, a blessed wife to the love of her life, and a Mission Control flight controller at NASA. Originally from Wisconsin, she now resides in Houston, Texas.

Twitter: @KMPohlkamp


  1. Replies
    1. This comment has been removed by the author.

  2. Interesting read.

    Also interesting that you removed your own post. Are you having a little DID with your Kara and K.M. personas?

  3. Very intriguing! I like the fact that you dug deeper and came up with a creative solution for your assassin.

    1. Thank you! I hope you'll consider checking out the novel :)

  4. Despite a vast pile of books to read, I have now bought this and moved it near the top. Thanks, K H or should that be Kara -an inspiring post. Now to find a suitable victim...

  5. Aconite roots will be nicely naturally stored in the ground over winter. Not so dramatic, but not such a good read.


Note: Only a member of this blog may post a comment.