Great Magnolia Garden Watch launched by Royal Horticultural Society

Thursday 26 February 2015

Gardeners invited to chart the flowering of magnolia trees to herald the start of spring

The Royal Horticultural Society (RHS) is asking gardeners to help them chart the onset and progress of spring by recording when Magnolia campbellii trees bloom.
Magnolia campbellii are among the tallest of all flowering magnolia trees, with large (30cm/12in across), pink (sometimes white) 'cup-and-saucer' flowers that usually open just before the leaves.

In recent years the opening of magnolia blooms in Cornwall, which locally heralds the arrival of spring, has been as much as a month earlier than the Met Office’s official date for the start of season, which this year is 1 March.

The flowering of the trees, which is considered a more specific indicator than daffodils of when spring has sprung, traditionally occurs first in Cornwall due to the county enjoying the longer days and higher temperatures needed to trigger flowering.

But with urban microclimates and milder winters, the RHS is keen to find out if Magnolia campbellii are flowering early in less traditional areas. This information will help the charity map the progress of spring across the UK and help gardeners to better understand the unique climatic conditions of their area.

In addition to asking gardeners to record sightings of the blooms by completing a short survey, the RHS is working with seven head gardeners in the Great Gardens of Cornwall group to document the flowering dates of specific Magnolia campbellii trees in their gardens. When all seven trees have 50 open blooms the project will announce the arrival of spring in Cornwall.

Speaking about the survey, RHS Executive President Jim Gardiner says: “The flowering of the Cornish magnolias should be on everyone’s must see list. The scale of these trees and the beauty of their spring buds opening is a magnificent sight.

“I’m delighted that that the RHS has been able to get more closely involved with the 2015 official countdown to spring and are really excited to see the results of the national survey.”

Gardeners are invited to take part in the survey by visiting:


Notes to editors

For more information, please contact Garfield Myrie in the RHS Press Office on 020 7821 3060or email

Cornwall is home to a Plant Heritage National Plant Collection of magnolias* at Caerhays Castle Gardens. Standing over 80 feet tall, with the largest girth on record, the 100 year old Magnolia campbellii in the grounds of Caerhays Castle normally bursts into a canopy of pink petals between 10 and 20 March each year.
 * Magnolia species in sections Buergeria, Magnolia, Oyama, Rhytidospermum, Tulipastrum & Yulania.

The seven gardens taking part in the project, all part of the Great Gardens of Cornwall Group, are: Caerhays Castle, Trebah, Tregothnan, Trewidden, Trewithen, Trengwainton and The Lost Gardens of Heligan. Follow Cornwall’s spring story at: 
Use the following address to share images of Magnolia campbellii in bloom:
@The_RHS using #hellomagnolia

About the RHS
The Royal Horticultural Society was founded in 1804 by Sir Joseph Banks and John Wedgwood for the encouragement and improvement of the science, art and practice of horticulture. We held our first flower shows in 1820, were granted a Royal Charter in 1861 and acquired RHS Garden Wisley, our flagship garden, in 1903. From our first meetings in a small room off London’s Piccadilly, we have grown to become the world’s largest gardening charity.

Today the RHS is committed to providing a voice for all gardeners. We are driven by a simple love of plants and a belief that gardeners make the world a better place. 210 years on we continue to safeguard and advance the science, art and practice of horticulture, creating displays that inspire people to garden. In all aspects of our work we help gardeners develop by sharing our knowledge of plants, gardens and the environment.

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About the RHS

The RHS believes that gardening improves the quality of life and that everyone should have access to great garden experiences. As a charity we help to bring gardening into people's lives and support gardeners of all levels and abilities; whether they are expert horticulturists or children who are planting seeds for the very first time.

RHS membership is for anyone with an interest in gardening. Support the RHS and secure a healthy future for gardening. For more information call: 0845 130 4646, or visit

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