A significant decline in bees has been widely reported in the press in recent years. The decline is due to a range of factors connected to human activity. These factors include the increased use of pesticides. Pesticides are chemicals designed to kill insects with the intention of protecting crops from ‘attacks’. As bees are insects, insecticides have a negative impact on them, even if they are not the insects that create difficulties in relation to crops.
Another impact is agricultural intensification. Greater intensification of agriculture leads to less diversification of crops, which means fewer habitats to support bees. One impact is the loss of wild meadows and changes in the management of these with a movement from hay to silage. This means there is less food available for bees throughout the foraging season, when bees need both nectar and pollen.
Add in climate change and even fewer appropriate wild habitats for bees are available. This means their suitable habitats are fragmented, suitable locations are isolated and bees are unable to travel to other appropriate foraging sites. This results in a poor picture for bees, but why is this so important? Should we worry about this decline in the bee population?
Bees have a very important role as pollinators. They are valuable for agriculture and also more natural settings. Pollination is viewed as an ecosystem service - a service of value to humankind that the natural environment provides.
So what can we do to help bees in our back garden?
With over 15 million gardens in the UK, there is a huge opportunity for gardens to provide ‘green corridors’ between other bee friendly habitats. By including bee friendly planting, or even a bee apartment block, you can allow bees to move between the diverse habitats they need. The bees we are considering here are ‘solitary’ bees, rather than honey bees established in hives. These solitary bees are not as social in the way that bumblebees are, but with over 200 species in the UK, they are very important pollinators. Bees need both nectar and pollen as well as food and shelter. By planting wisely you can provide these and create effective 'green corridors'.
Selecting where you are going to plant vegetation for bees is important. Bees like shelter from the wind but also, as they are cold blooded, like to feed in full sun. Planting flowers that bloom throughout the year is also helpful for bees. This makes pollen and nectar available throughout the seasons for the bees, and it has the added benefit of making your garden beautiful all year round. It is also important to avoid using insecticides and pesticides in your garden. If you have to use them make sure that you do so in the evening when the bees are safely in their hives.
There are lots of species of plants that provide a good source of pollen and nectar for bees these include:
- Shrubs – such as hebe, weigela and buddleia (traditionally known as the ‘butterfly home’). Shrubs have the advantage of providing good structure for birds too.
- Lots of perennials also provide pollen and nectar – such as campanulas and hellebores. Perennials are great for gardens as they grow back year after year. Once you have planted them you provide a food source for bees every year, and also great ground cover without needing to plant every spring.
- For winter flowers, particularly if you have more challenging acid soil, some heaths and heathers provide flowers during the autumn and winter seasons. This provides pollen and nectar for bees still active then and also flowers in your garden later in the year.
A bee apartment block, often referred to as a bee hotel, is a place where bees spend much of their lifespan - making it more of their home than the name 'hotel' implies!
Bees emerge from their nest in the bee apartment in spring. After mating, the female finds her own nest location. In each site, the bee lays a single egg and then seals that chamber. The bee lives for just over a month and lays around 20 eggs in this time. Throughout the summer the eggs develop, first into larvae and then a cocoon for the winter. The next spring a new bee emerges.
A bee apartment, like bee feeding areas, should be located in full sun to allow emerging bees to warm their bodies. It should also be firmly fixed, bees do not like movement. It should be located high up to avoid vegetation shading it and also predators eating the larvae.
You can build a bee apartment using natural materials in your garden to help the solitary bee. Make them using a wooden box or old plant pot and filling this with pine cones, small pieces of deadwood and straw or cut canes. Tightly pack these, using a variety of sizes (up to 10mm in diameter) making them ideal for bees but also other insects. For those feeling more adventurous, you can also drill holes in a piece of wood. As bees prefer smooth, closed tunnels, make sure that you only drill part way through. Sanding the edges is also helpful to avoid damage to bee wings as they enter and exit the hole.
Maintenance of the bee apartment is important. Cleaning this out every year prevents parasites infesting the space. Do this by restocking it with fresh material to make sure it is a space for healthy bees.
Remember that bees do not like the wet. If it is a wet winter you may need to move the bee apartment to a drier location from October through to early March. If you do this, make sure that the location, such as a garden shed, isn’t too warm as bees need the cold over winter.
As well as supporting bees in your garden you can also help gather information about bees through citizen science activities. For example see: https://www.bumblebeeconservation.org/surveys/