… a blog by Buglife Development Officer, Beth Barber.

Did you know that there are 23 million gardens in the UK? In England alone, gardens make up the 3^rd largest land-use group by area, the land of which equates to covering 4.5 times more area than all the National Nature Reserves in the country. We can all make a huge difference in our gardens with small adjustments to attract and support solitary bees.

When most of us think of a bee, we probably picture a big furry bumblebee, or perhaps an industrious hive of honeybees, but 240 out of the 270 bee species found in the UK are solitary bees: they don’t produce honey or live in social colonies and many of them aren’t even striped black and yellow.

In solitary bee species, each female creates a nest comprising a series of compartments or cells into which she lays her eggs. Egg cells are provisioned with a supply of nectar and pollen and then sealed using earth, chewed up vegetation or, in some species known broadly as cellophane or plasterer bees, using abdominal secretions. Although each nest and the egg cells within it are created by a single individual, nests may occur in aggregations particularly if they are sited in a favourable spot, and some species may even share a communal nest entrance.

Female and male solitary bees are both important pollinators. Unlike honeybees and bumblebees, many solitary bee species don’t mix the pollen they collect with nectar meaning that they carry pollen as a loose dry powder all over their bodies which facilitates the transfer of pollen grains between flowers. Estimates suggest that a single Red Mason Bee (Osmia bicornis) provides the same level of pollination services as 120 worker honeybees!

Which solitary bees might you see in your garden?

Hairy-footed Flower Bee (*Anthophora plumipes*) © Nick Packham

Solitary bees are generally peaceful creatures, having neither queen nor stocks of honey to defend and this combined with their efficiency as pollinators makes them welcome garden visitors with many species favouring urban parks and gardens. Mason bees are aerial nesters preferring old wood, soft mortar, and hollow plant stems although they may also occupy bee hotels. Red Mason Bee visits many species of plants including fruit trees, willow and dandelions. Tawny Mining Bee (Andrena fulva) favours many of the same plant species but is a ground nesting species making its nests in light sandy soils. Ashy Mining Bee (Andrena cineraria) is another common garden visitor which leaves a characteristic small pile of earth outside its chosen nest site – a landmark that is commonly created by mining bees. The Patchwork Leafcutter Bee (Megachile centuncularis) is found in lots of different habitats but is especially common in garden settings. This bee has large jaws to cut neat semi-circles out of rose leaves which it uses to line and seal its egg cells. If you garden in the south or east of England you may be lucky enough to spot the evocatively named Hairy-footed Flower Bee (Anthophora plumipes). This species is a long-tongued bee which favours tubular flowers such as Lungwort, Red-dead Nettle or Comfrey and it nests in old walls or sometimes bare ground. Cuckoo or nomad bees are parasitic species which lay their eggs inside the nest of their host. When the eggs hatch, the larva kills the host larva and feeds on the stored pollen and nectar before emerging to repeat the cycle.

How can you improve your garden for solitary bees?

To attract solitary bees to your garden, you will need to provide pollen and nectar-rich plant resources alongside suitable nesting sites. Often the next generation will return to the same nest site so it is important to provide continuity of nesting habitat and floral resources in the garden from one year to the next.

Solitary bees are active from early March until late October depending on species so select plants to extend the flowering season. Experiment with early flowering spring bulbs, pussy willow and climbers such as Clematis cirrhosa at the beginning of the season while Sedums, Michaelmas Daisies and ivy all flower well into autumn. Choose plants with a variety of flower structures including long tubular flowers such as salvias and honeysuckle to attract long-tongued bees like mason and leaf-cutter bees. Bell-flowers and plants in the daisy family appeal to short-tongued bees like Colletes and Lasioglossum spp. Avoid double-flowered cultivars where sheer volume of petals makes it hard for bees to access the nectar within. Try to include at least some native plant species and consider leaving some wild areas around the edges of the garden to be colonised by weed/wildflower species such as dandelion, clover, red dead nettle and buttercup.

European Wool Carder Bee (Anthidium manicatum) © Suzanne Burgess

Some plants will attract specialist bees. For example, Campanula species, particularly cultivars of the three native bellflowers, C. glomerata, C. trachelium and C. rotundifolia, will attract Campanula Bees (Melitta haemorrhoidalis) and Scissor Bees (Chelostoma campanulorum) both of which can occasionally be observed having a snooze within the flower on an overcast day. The Yellow Loosestrife Bee (Macropis europaea) uses the floral oils of Yellow Loosestrife (Lysimachia vulgaris) to create a nectar-pollen mixture for her larvae and, the Wool Carder Bee (Anthidium manicatum) uses the hair from felted plants such as Lamb’s Ears (Stachys byzantina and S. olympica) to line her nest. If you grow ivy in your garden you may well attract the Ivy Bee (Colletes hederae) which was first found in the UK in 2001 but is now widespread in southern England.

In terms of nest sites, most species require a warm, sheltered spot with readily available nesting materials and plentiful floral resources nearby. Ground nesting species tend to favour light, dry soils in a sunny spot such as bare earth on a south-west facing slope or footpath, although Tawny Mining Bee will nest in short turf. Aerial nesters require standing deadwood, plants with hollow or pithy stems such as bramble, elder, artichoke or sunflower (these stems can be left stacked to the side of the compost heap when cut back), sunny walls and fences. Bee hotels should be positioned in a sheltered spot and, if you are constructing your own hotel, make sure to include a variety of different diameter holes to attract different species.

Finally, avoid use of pesticides in the garden. This is an easy change for us all to make that will positively impact solitary bees as well as other wildlife species who use your garden.

You can find more ideas and guidance on ways to create a solitary bee friendly garden in our Gardening for Bugs hub.

Join us & celebrate the wonderful world of solitary bees!

90% of bee species are solitary bees and along with other pollinating animals their hard work is responsible for at least one in every three mouthfuls we eat. However, like many species, they are under threat and need our help.

We invite you to Earn Your Stripes by pledging to help the bees, Wear Your Stripes for a day, or the entire week, and Share Your Stripes by helping us to raise awareness and share your activities, solitary bee facts and photos across your socials this Solitary Bee Week