Help us to increase the local population of the brilliant Brimstone Butterfly
The Brimstone butterfly (Gonepteryx rhamni) is one of the heralds of spring, and can be seen in most parts of Sheffield and Rotherham. Despite having simple needs the population size in our area is very small. This can be easily changed, its population can explode in size, simply by planting sufficient numbers of its larval host plant, Common Buckthorn (Rhamnus cathartica).
To do this we need your help! In partnership with Nether Edge and Sharrow Sustainable Transformation (NESST) we are asking people in Sheffield and Rotherham, like yourselves, to plant Common Buckthorn in your garden or other green spaces that you are responsible for.
All you need is a 1.5 metre x 1.5 metre x 1.5 metre space for each plant, which is sufficient space for the plant to reach a large enough size for the Brimstone to lay its eggs.
How you can join in
- We will be placing a bulk order for bare root Buckthorn whips in November 2021
- The price of each Buckthorn whip is just £3
- Delivery of the bulk order will be to the Sheffield and Rotherham Wildlife Trust headquarters: Victoria Hall, 37 Stafford Road, Sheffield, S2 2SF
- Once they’ve been delivered to us, we’ll contact you and ask you to choose a time slot to pick up the whips you have ordered
- To join in, simply:
- Decide how many Buckthorn whips you want
- Complete your order form here , before 31st October 2021 to pick up your whips in November
- We will be in touch shortly after you submit your order to arrange online payment
- When the delivery arrives in November 2021 will contact you again with a range of dates/times which you can choose from to collect your Buckthorn plants from the Sheffield and Rotherham Wildlife Trust headquarters
- You will receive an aftercare leaflet with your Buckthorn plants
Together we can increase the population of the Brilliant Brimstone Butterfly!
The Brimstone Butterfly
The Brimstone butterfly is bright yellow in colour, large, and is hard to mistake for anything else in the UK. Adults hibernate over winter, often hidden under Ivy leaves. They emerge in early spring, usually on warm days in February to April, and are usually seen flying fast and direct, as if on a mission to somewhere.
After mating, the female lays her eggs on Buckthorn, and the eggs usually hatch within 10 days, depending on the temperature.
The caterpillar feeds on the leaves of the Buckthorn plant over a period of one to two months usually in May and June, before pupating, and emerging as an adult butterfly in late July and August, when they are often seen nectaring on plants such as Thistle. The cycle then begins again, with the adults hibernating over winter.
There are three native Buckthorn species in the UK, namely Common Buckthorn (Rhamnus cathartica), Alder Buckthorn (Rhamnus frangula) and Sea Buckthorn (Hippophae rhamnoides).
The Brimstone butterfly lays its eggs on the first two of these, exclusively.
Alder Buckthorn only tends to thrive on waterlogged acidic soils, so for most gardens and sites, the best plants to buy to attract the Brimstone butterfly is Common Buckthorn, which is also sometimes known as “Purging Buckthorn.”
Common Buckthorn has small yellow/green flowers in May, which when pollinated, turn into 6-10mm diameter purple/black berries in the autumn.
If you want to let Common Buckthorn grow, completely unconstrained, it can grow into a small sized tree, with a height of 6 metres to 7.5 metres. However, it can be pruned quite happily in late winter, to keep it smaller.
To attract the Brimstone butterfly to lay eggs, all you need is a 1.5 metre x 1.5 metre x 1.5 metre space for each plant.
The aim of the initiative
The aim of this initiative is to demonstrate that very small practical steps, such as the planting of a larval host plant, can have large demonstrable impacts.
We are building on the success of a similar initiative which began in East Suffolk in 1998. The Brimstone butterfly was very rare there at the time. Over the course of five years, over 2000 Buckthorn plants were planted in Ipswich and the surrounding area.
As the Buckthorn plants grew, so did the Brimstone butterfly population, and by 2010, the population was described to have “exploded.” The Brimstone is now a very common butterfly in East Suffolk.
We want to do the same in Sheffield and Rotherham. We know it won’t be an overnight impact. But we know that in roughly 10 years time, if we plant enough Buckthorn plants in Sheffield and Rotherham, we will also see the local Brimstone population “explode” – we can’t wait!
(c)Gillian Day and Suzsanna Bird