21 September 2018

Propagation: Growing something that's never been grown before

Ed Ikin, Head of Landscapes and Horticulture, explains how Wakehurst has stepped up to the challenge both in the nursery and in the grounds.

By Ed Ikin

Horticulturalists working at Wakehurst in the nursery

Nurturing plants in our nursery

From Madagascan palms to English waterlilies, we grow and nurture a huge variety of plants in the nine glasshouses of our nursery.  

Many of the plants we grow in the nursery are critically endangered, such as the Madagascan suicide palm (Tahina spectabilis). This species was only discovered in 2006 and there are less than 40 mature plants known to be growing in the wild. 

We nurture these plants in environments that are as close as possible to their natural habitats to ensure they thrive.

Half of the nursery’s capacity is dedicated to growing plants for Kew’s scientific research, while the rest is for garden ornamentals and propagating the rarer elements of our living plant collection. 

A high-tech growth chamber

We grow many plants that are rare in the UK, and most of them are rare for a reason – they’re often tricky to grow, with complex requirements for germination. 

Wakehurst’s high-tech growth chamber is the essential tool that helps us germinate and grow hard-to-grow species. 

The chamber is capable of maintaining the precise temperature, light and humidity regimes that allow rare plants to grow. 

Our mission includes banking, growing and sharing indigenous UK flora for habitat restoration, and the growth chamber helps us do this. For example, we grew a key grassland species called dyer’s greenweed (Genista tinctoria) for meadow restoration schemes in the UK.  

A success story: the least waterlily

The least waterlily (Nuphar pumila) a UK native aquatic, is in urgent need of conservation. In England it’s found in only one lake in Shropshire.

In less-than-glamorous conditions, an intrepid botanist dived into the aquatic murk in Shropshire and collected seeds and root material, which were brought to the nursery. 

Botanical horticulturist Jo Walmisley then successfully recreated the conditions that the water lily grows in.  

By recreating a low light, low temperature, and moderately oxygenated conditions, the water lily was successfully germinated and rooted. 

This precious dwarf waterlily is now well placed to challenge its common name.

A new Chilean woodland: conserving the endangered monkey puzzle tree

In 2009, propagation manager Jo Wenham went on a collecting trip to Chile and brought back the seeds of the iconic and endangered monkey puzzle tree (Araucaria araucana). 

Unfortunately, the seeds couldn’t be stored in the Millennium Seed Bank (MSB), as some seeds can’t enter full dormancy in a chilled environment. 

Jo’s answer was to raise hundreds of young monkey puzzle trees from seed and plant them out in a new Chilean woodland at Wakehurst.

This planting will be a future living conservation resource, but is banked in Wakehurst’s landscape rather than in the vaults of the MSB.  

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