We are well into autumn and touching the toes of winter, and you will see fewer pollinators around. Discover what is going on in Pollinating London Together’s latest newsletter.
Though the pollinators have started to disappear for the winter and many are tucking themselves in for hibernation, we are still busy continuing our work. Since our last newsletter, we have participated in the Urban Nature Project at Camley Street with the Natural History Museum, the Discovery Day at Hampton Court Palace, and it was lovely to see so many of you at our Inner Temple event, where our patron David Domoney gave an engaging talk.
Our Pollinator Ecologist, Dr Konstantinos Tsiolis, was awarded his PhD in September, which is a great achievement. Konstantinos has now finished his final round of surveys across the City of London. He has taken on a mammoth task this year, surveying a total of 60 sites four times. That is a total of 240 surveys undertaken!
Konstantinos is now busy collating and analysing the data for preparation of the annual report.
Apprenticeship Discovery Day
The Apprenticeship Discovery Day is an annual event. It is designed to bring horticulture apprentices from around the UK to spend a day with peers and share experiences and learn more about potential careers. There is a wide range of careers open to those who have trained in horticulture. Venues in the past have included RBG Kew, RHS Wisley and the legacy Olympic Park. In early October we were at Hampton Court Palace – a lovely venue with input about the history of the nature of the gardens over time. There were around 150 apprentices and 50 school students, and during the lunch break, from their stand, Konstantinos and Heather were able to talk about the need to support pollinators. Again in the afternoon, when they were stationed in the kitchen garden, they were able to talk to groups as they were led around the grounds by group leaders. Konstantinos caught some of the last pollinators of the season which is always a good talking point.
Inner Temple event
It was great to see so many of you at the Inner Temple event back in September.
The evening started with tours of the garden, led by the immensely knowledgeable team of gardeners at the Inner Temple. The talks discussed the history and planting of the gardens, with a chance to walk along the gravel and treelined paths and to see the succulent plants in the greenhouse. Konstantinos was present with his fascinating collection of bee specimens and answered any pollinator questions that our guests had.
In the City of London, forage can be limiting especially if there is a lack of suitable flowering plants. Spaces like the Inner Temple gardens provide an important refuge to these pollinators, where they can gather the resources they need to survive and thrive.
The gardens have an incredibly rich history, with links to Shakespeare as well as hosting London’s numerous premier flower shows. The Inner Temple’s archives show that the first recorded gardener was appointed in 1307, at which time it was described as an orchard. Over time, the gardens developed, becoming more ornamental with plants such as roses in addition to the lawns and fruiting trees. Alongside this, greenhouses were installed and landscaping undertaken to form embankments and the addition of a terrace in 1591. All these changes and modifications over the centuries have helped to form the attractive gardens we see today.
The evening progressed inside, with an introduction from our Chairman John Burton, followed by one of our patrons, chartered horticulturalist and broadcaster David Domoney. The talks were inspirational and insightful, discussing the challenges around gardening for pollinators, but also how we can tackle pollinator declines both as individuals and corporations.
A big thank you to Gravis Capital Management, one of our corporate members, for sponsoring the event and the team at Inner Temple for their support in making the event a great success.
What happens to bumblebees in winter?
Hibernation can be observed in many species, from mammals to invertebrates, and is defined as a state of minimal activity and slowed metabolic state which commonly takes place over the winter season. In its most simplistic term, it’s when species tuck themselves away for the colder months to aid their survival into the warmer seasons.
Autumn brings cooler temperatures and a change in the seasons. For bumblebees, this means preparing for hibernation, although some species, like the common carder bumblebee (Bombus pascuorum), can be seen flying later in the season due to a delayed hibernation, they may be spotted flying on warmer, sunnier days.
During autumn, bumblebee colonies start to shrink; the worker bees, males and older queens will die off in an annual life cycle. However, new queen bumblebees who have mated during the summer will be searching for places to hibernate over winter.
Bumblebees will choose certain locations to hibernate safely and escape the frost. These include – but are not limited to – holes in the ground, in dead plant stems, under piles of leaves, bee hotels and compost heaps. Some have even been observed hibernating in old bird boxes and long grass. Often bumblebees will choose north-facing banks, so they avoid being woken too early by the winter sun.
In recent years, climate change has led to milder winters. We are seeing more and more overwintering nests, where bees do not go into full hibernation. This has been observed in a few species like the buff-tailed bumblebee (Bombus terrestris) and early bumblebee (Bombus pratorum). Typically, overwintering nests are seen more in southern counties and urban areas where extremes in temperature are lessened and winters are often milder.
There are ways to help bumblebees and other pollinators during the shift in seasons – for example providing shelter in the form of log piles and leaving the grass to grow longer. It is still important to provide plenty of food resources by growing nectar-rich plants. Winter-flowering plants like heathers and snowdrops can really help bumblebees who may be overwintering or emerge on warmer winter days.
It is very important that if you stumble upon a hibernation or overwintering nests you do not disturb them and if you accidentally do, put everything back as you found it. This will help the bumblebees to survive the colder months.
In spring, as the temperatures rise again, bumblebees will emerge from hibernation and continue their life cycle once more.
Pollinator Guide – Red mason bee (Osmia bicornis)
Solitary bees are a diverse group of pollinators, living out their lives individually rather than in a colony like some bumblebees.
The red mason bee is one of the more common of the solitary bee species, identifiable by its small body, with a gingery and ‘fluffy’ appearance, though very difficult to differentiate from other mason bees unless you have a keen eye. Males are smaller than females; this is known as sexual dimorphism, which is common in many species. The red mason bee can be seen from late March until late summer, and feeds solely on pollen and nectar. They are widespread across England and Wales, but are less common in Scotland.
These bees can be spotted going in and out of crumbling brickwork or small gaps in buildings during the summer months, but they are not limited to just masonry! They can also be found nesting in bee and bug hotels, old plant stems and anything that provides a suitable nest site. You can encourage them into your garden with things like bee bricks, bug hotels and even a tin can filled with short hollow tubes.
Nesting sites are very important for red mason bees, as their life cycle relies on finding a suitable place to lay their eggs and for their larvae. After mating, the female bee will build its nest, lining it with mud, pollen and even leaves. She will lay one egg in each tube-like nest structure (such as that in a bug hotel), barricading the egg into the tube. The larvae will then hatch and develop and pupate over the autumn months and hibernate during winter, all within the tube, known as a ‘cell’. In the spring, when temperatures increase, these new red mason bees will emerge from their cells and the life cycle will begin again.
It has been estimated that it can take an entire colony of honeybees (about 20,000 bees) to pollinate one acre of apple orchard, but roughly 250 solitary bees. Solitary bees are fantastic pollinators, and are responsible for pollinating plants like holly, ivy and mistletoe! Very festive bees indeed.
22nd February 2024 – Join us for an evening lecture with Professor Alistair Griffiths, where he will be referencing the importance of pollinators and their relationship to greenspaces and wellbeing. The lecture will be followed by drinks and canapes.
Alistair is the RHS Director of Science, a Fellow of the Institute of Horticulture and a board member on PlantNetwork.
Alistair leads a highly skilled team of scientists who are focused on assimilating and evaluating the most current scientific knowledge and undertaking scientific research that provides high-quality evidence-based advice and solutions to address horticultural challenges so as to foster and improve beginner, amateur and professional gardening experiences. He is responsible for ensuring that the RHS charity remains at the forefront of horticulture science.
Alistair loves to inspire, motivate and engage people about the role of plants and horticulture in benefiting the environment and our health and wellbeing. His ambition is to build a more resilient gardening community who enjoy their gardens whilst reducing their impact on the planet.
Tickets are available here.
Location: Mercers Hall, Ironmonger Lane, EC2V 8HE
Save the date
2nd April – PLT Annual Meeting – Drapers Hall