Mission bumblebee

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Bumblebee on lavendar

Bees are my favourite garden visitor. As I planned my garden, I decided one of my success ratings would be to walk out in to my garden at any point during daylight hours, and hear a bumblebee. Early bumblebee worker collecting food from geraniums in my garden
It may seem strange to give myself a ‘performance target’ for bees in the garden, but it has helped me to identify gaps in the flowering year where my garden is not acting as a useful food source. I used the Bee Kind tool to identify the bee-friendly plants in my garden. The tool reviews your plants, and provides ten recommended plants to help your garden become more bee-friendly. Further advise is available from Bumblebee Conservation Trust.

Mission No. 1: Ensure my garden has a good source of nectar and pollen close to chosen bumblebee nesting sites.

The most critical time of the year for bees is when the queen bee is raising her first brood. In early Spring, she will emerge from hibernation and start to forage, and when she is ready, she will look for suitable locations to build her nest, creating a wax honey pot in front of her, and then produce her first brood. She raises her body temperature to 30 degrees Celsius to keep them warm, and to allow her to fly during the cold and damp months. Spring-flowering plants, such as hellebores, pulmonia and crocuses, are so important for this challenging time, when she needs to visit thousands of flowers a day. She needs to collect a huge amount of food to keep her energy supplies topped up. She is single-handedly raising her children, and she can only be out of the nest for short periods otherwise her brood will perish. Once the first brood of workers is raised, then she will not need to leave the nest again, as they will forage for her.

Bees expend a huge amount of energy in flying. But they need to fly to collect energy, so they aim to collect the most nectar and pollen they can in the shortest amount of time. To optimise their foraging flights, bees learn how to access the nectar of a type of flower, and then look for the same flower in the same area, so that they can quickly collect food without needing to work out how each flower works. This means that if you only have one small nectar-rich plant that doesn’t flower for very long, it may not attract the bees you were hoping for. However, if there are several of the plants in the same area, it will get visited more regularly. Planting a patch of the same flowers allows bees to quickly gather a large amount of food without flying long distances.

Other important spring-flowering plants include lupins, comfrey, vetch and fruit trees.

The second most important time for queen bees is when the next generation emerge from the nest and need to gather enough food to get fat enough to survive winter. A good nectar-rich supply of late summer and early autumn flowers should help the queen bees to hibernate for winter. Some bumblebees may be seen foraging in mid-winter. Winter-flowering plants such as mahonias can help provide the additional boost of energy these bees need.

For more info about the fascinating bumblebee life-cycle, see link.

Mission No. 2: Support a wide range of bumblebee species

Individual bumblebee species have different flower preferences, which can be partly explained by the length of their tongue. The short-tongued bumblebees are more generalist, and appear to survive better in urban environments. The medium and long-tongued bumblebees are specialised for flowers with long corollas (tubes). Short-tongued bumblebees can rob the nectar from these longer corolla plants without pollinating it by eating a hole in to the side of the flower, bypassing the pollen. Without the long-tongued bees, many of these flower species would be lost.
The small garden bumblebee (Bombus hortorum) is the only long-tongued bumblebee that remains common in the UK. If this species were to decline, we could lose a number of long-tubed wild flowers that can only be pollinated by these long-tongued bees. Garden plants that have long corollas include cowslips, wild honeysuckle, larkspur, monkshood, delphinium, comfrey, cerinthe, foxgloves, vetches, lavender and aquilegia. Red clover is thought to be an important food source, hence organic farming that use legumes as part of crop rotation can greatly increase the number of garden bumblebees. They need flower-rich meadows to thrive, but with greater numbers of wildflowers along verges, urban areas may provide a temporary respite from the intensification of agricultural practices in the countryside.

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Bee visiting Nasturtium.

The common carder bee (B. pascuorum) is the only common medium-tongued bumblebee in the UK. They are fond of labiates such as white dead entitle (Lamium album) and vetches (Vicia spp.) They nest above ground in tussocky grass, and they do not travel far to gather food (a doorstep forager), so they require suitable nesting sites and food sources in close proximity.

Most other common garden species in the UK have short tongues, including the Buff-tailed bumblebee (B. terrestris), White-tailed bumblebee (B. lucorum), Red-tailed bumblebee ( B. lapidarius), Early bumblebee (B. pratorum) and Heath bumblebee (Bombus jonellus). These are more generalised feeders and forage more widely. They tend to forage on daisy-type flowers, and prefer flowers that form a landing platform, such as daisies, dandelions and thistles.

Whilst we have lost several bee species in the UK, we have also recently gained a new coloniser from Europe. The Tree bumblebee (B. hypnorum). I saw many tree bumblebees in my Cardiff garden during summer 2014. Their success appears to be their ability to take advantage of bird nesting boxes as nesting sites.

A hive of tree bumblebees gathering nectar and pollen from the large purple flowers of this geranium

A hive of tree bumblebees gathering nectar and pollen from the large purple flowers of this geranium

Plants I would highly recommend for bees in the garden:

Pulmonaria (Lungwort): It is pure entertainment to watch bumblebees try and wrestle in on the food source for the hairy-footed flower bee, which seems to guard its patch of lungwort in my garden. This plant provides forage from February. A lovely spotty-leaved plant that deserves a place in every garden.

Ajuga (bugle): An early flowering carpet plant that attracts pollinating insects from miles around.

Dandelions: I let them flower with the forget-me-nots and tulips to create a refreshing Spring colourfest. While most people see these as an absolute enemy, I’ve decided to love them, but for the rest of the year I remove the plants as I see them, but there will always be a fair number of these lovely flowers that get through. Flat headed flowers such as these are important for short-tongues bees to walk across.

Foxgloves: A beautiful sight watching bees work their way around the flower stalks.

Perennial geraniums: An absolute must, their open flowers are covered in all sorts of bees.

Flowering herbs: I grow as many herbs as I can, as they are always shrouded in bees. Chives, rosemary, sage, thyme, winter savory, oregano, lavendar, and all others.

Raspberries: A long-flowering fruit shrub, great for me, and the bees.

Nasturtium: A vigorous climber that reseeds itself every year in my garden, flowering from August through to the first major frosts.

Climbing Ivy: It needs to be controlled to avoid outgrowing its allocated space, but ivy is covered in hoverflies and bees throughout its flowering period, and then supports berry-eating birds through winter, that it is worth the effort. I have a garden wall coated in ivy that I hack back occasionally to keep it away from the house wall.

For further advice, see  RHS Plants for Pollinators and Bee CauseEven if you don’t have a garden, you can still help bumblebees by getting involved in bumblebee conservation.

Other things to consider…

When reviewing maps of bumblebee distributions in the UK, we appear to be in a unique position in Cardiff. Many less common bumblebee species are located along the warmer coasts of Wales and Southern England. Cardiff could create an impasse between the Gwent Levels and the Vale of Glamorgan and beyond. There are localised strongholds for rare bee species near to Cardiff, and we can all help to avoid the decline of biodiversity through our choice of acceptable agricultural practices. For example, the Shrill Carder Bee (Bombus sylvarum) is a rare species, which is unlikely to visit urban gardens. Buying organic food can reverse the negative impact intensive agricultural practices are having on our bumblebees. See this link to the Soil Association that shows dramatic evidence that organic practices can help save our bees. In addition, you could also volunteer to help manage local environments where these species do still thrive. For more information, please visit the Wildlife Trusts page on shrill carder bees.

Suitable bumblebee nesting sites are critical for their survival. Hedges can be important nesting sites for some species of bumblebees, as they provide an undisturbed area of ground. Mixed native hedges can also provide a huge source of nectar and pollen immediately next to the nest sites.

I’d be really interested to hear from others who are looking to support our bees in their gardens, and particularly if you have had success in creating a bumblebee house that has been occupied…

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