Plants and Bees
A 100m year old love affair…
Flowers to pollinators are as vital as oxygen to breathe and each is essential for the other’s survival.
Plants and their pollinators have evolved together across the planet for around 100m years to the point where over 90% of all plant-life across the planet reproduces through pollination by insects (and occasionally animals). This transfer of pollen is facilitated by attracting as many pollinating insects to visit the plant’s flowers as possible by providing them with a source of food in the form of pollen itself along with a sugar-rich liquid called nectar.
Bees are generally one of the largest and most important group of pollinating insects and forage is the term used to define the plants visited by bees from which they collect their food.
Pollen is a rich source of protein, fats and vitamins and is particularly important for bees and other insects when raising young but also used for body repair, gaining weight prior to winter and for entering breeding conditions. Nectar is a source of high-energy carbohydrates in the form of various sugars. Bees use Nectar to fuel their bodies, power their flight muscles and other metabolic functions. Many bees also consume nectar and convert it into wax for use in nest construction forming cells or comb to raise their offspring or storing food for later consumption.
Honey bees collect vast quantities of nectar, over 500 lbs per colony per year and turn some of this nectar into honey which they store to eat during the winter months when the weather is too cool for them to fly and flowering plants are in scarce abundance.
Different pollinators have different flower preferences from which they like to feed. This is determined by their tongue length and the time of year they are active. Long-tongued bees prefer long tubular-shaped blooms or trumpet-shaped flowers, often flowers that are shaped like bells, such Fox Glove, Penstemon and Comfrey.
Short-tongued bees prefer simple open flowers with easy-to-access nectar such as orchard tree blooms, dandelions and daisies. Honey bees are generalists, having short-ish tongues, being active most of the year and feeding on a wide range of flowers.
When do bees need access to flowers?
Pollinators are most active from March to October and require pollen and nectar throughout this active period. Some species such as the Buff Tailed Bumble Bee are active all year round in southern parts of the UK and rely on winter flowering plants such as Mahonia, Viburnum Tinus and Winter Honey Suckle for forage during the cold months of winter. These bees rely almost exclusively on exotic garden plants for survival during the winter months when our native plants are mostly dormant.
Do bees discriminate between native plants and exotic flowers?
The majority of adult insects including most bees do not care whether or not a plant is native or non-native as long as its pollen and nectar are produced freely and are of good quality. For nectar, this means a high sugar content and for pollen, it means a high protein content and presence of fatty acids and oils.
For many years conservationists and wildlife gardeners have advised that natives are best planted to attract and provide food for pollinators in our gardens but recent research increasingly supports the opinion that mixtures of native and non-natives are actually better. This is because the majority of our native flowers are short-lived and flower in spring and early summer while many non-native plants help to fill the late summer and autumn gap, extending the flowering season and providing food for pollinators at a time of year when they struggle the most to meet their nutritional needs.
How much forage does a bee hive need?
This is a difficult question to answer but estimates suggest that a typical colony of honey bees requires around 500lbs of nectar and 100lbs of pollen annually just to meet their own reproductive and winter survival needs. This is more than a bathtub’s worth of nectar and is made from billions of flower visits by the thousands of workers that make up the colony.
And this is before the bees make any surplus honey for the beekeeper to harvest!
To make a 1lb jar of honey it is estimated that the colony will visit between 2-4 million flowers and fly up to 55,000 bee miles – that is twice the distance around the globe. In addition to the nectars which go into producing the honey, the bees also need to consume a lot of nectar themselves for the energy needed to generate the heat and circulating air currents within the hive to drive off the water content within the nectar and transform it into honey. So, the amount of nectar gathered in the production of the surplus honey the beekeepers take as a honey crop is astronomical.
To gather this vast quantity of nectar and pollen the bees must visit many billions of flowers and spread themselves over a large area. A colony will typically forage within a 3km radius from the hive but when forage is in short supply they will fly as far afield as 12km to find rewarding patches of flowers.
There can never be enough flowers to support our pollinators.
How can I best help bees?
Honey bees are currently faring well in the UK thanks to the efforts of an increasing number of amateur beekeepers who tend to their needs. Colony numbers are once again increasing with around 225,000 hives registered in the UK and numbers of beekeepers have risen from around 8500 to over 25,500 in less than a decade.
Whilst honey bees have beekeepers to help them stay fit and healthy finding sufficient forage and sufficient variety to provide them with a balanced diet is a constant challenge. So, planting the right sort of flowers for them in our gardens is a great way to help them.
Many of our 274 species of Wild bees, Bumble Bees and Solitary Bees are in serious decline and don’t have the luxury of beekeepers to tend to their needs. The best way to help them survive and prosper is by planting the right kind of flowers for them.
Plant a variety of flowers in your garden to cater for a variety of different bees. These can accommodate different tongue lengths. Choose a succession of flowering plants that will provide forage throughout a long season. You can further assist solitary bees by erecting nesting houses for them to rear their young in. These are available to buy from many good retailers but you can also make your own for little or no money.