a mediateam website

See a sample issue of The Irish Garden!

August 2011

To see a sample of the current issue of Ireland's best-selling gardening magazine, click the image below.

Accessing from an iPad? This edition is designed for PC and Mac access using Flash, which is not supported by the iPad. To access the iPad edition, search 'The Irish Garden' in the Apple app store.

Solitary bees

Dick Warner extols a little-known garden insect

Most gardeners know that bees are important pollinators, particularly of fruit trees and some vegetables. Most also know that bees are declining in numbers in Ireland and all over the world as a result of diseases, parasites and the over-use of insecticides. It's one of those depressing environmental stories. But there is also some good news.

The honey bee and, to a slightly lesser extent, the various kinds of bumble bees are particularly vulnerable because they are social bees that live in colonies. If something goes wrong - pest, disease or poisoning - the whole colony tends to die and the garden loses large numbers of pollinators. But there are 101 known species of bee in Ireland and only 14 of these are social bees.

The remainder are solitary bees and many of them are actually more efficient pollinators than the social bees. This is because they are small, smaller than a honey bee, so they can utilise a wider range of flower species when they're feeding and because they tend to emerge earlier in the spring which helps with the pollination of early-flowering crops, such as pears. They are relatively hairy, to keep them warm in a chilly Irish spring and dark in colour to hold warmth. In the United States some fruit growers use commercially traded species of solitary bee for pollination.

Some solitary bee species live in burrows, usually excavated in a dry sunny bank and about 10 to 15cm long. Others are opportunists and breed in cavities in walls, nail holes or even door locks. Yet others use hollow stems or canes. The young bees emerge from these early in the spring, the males first and then the females. They mate and then go foraging for pollen and sometimes nectar. Some will emerge so early in the spring that about the only source of food available is the pussy willow and the first dandelion flowers.

The mated females return to the nest site and lay individual eggs, each sealed in a little cell with a supply of pollen, sometimes mixed with a little nectar, to feed the larva when it hatches. The first eggs laid will hatch into females and the last few, in the cells nearest the mouth of the burrow, will become males. This is why the males emerge before the females in the spring.

You can buy nest boxes specifically designed for solitary bees or you can make them out of bundles of hollow stems or small calibre canes. You should put them in a sunny, sheltered, south-facing position - under the over-hanging eaves of the house or a garden shed is ideal -and the bees will find them very quickly. It's recommended that in cold winters you bring the nest boxes into a garden shed or unheated greenhouse for a month or two, putting them back outside in the early spring.

The females of most solitary bee species are capable of inflicting a very mild sting but they almost never do this. You would have to handle one very roughly to provoke it into trying to sting. And they are excellent pollinators which are quite fun to watch as they go about their business.

There are also solitary wasp species with somewhat similar life-styles. Wasps tend to be more omnivorous than bees, and many species are predators or carrion-eaters at some stage in their life-cycle. But they also utilise nectar and pollen and, although they're not as reliable or efficient as bees when it comes to pollinating apples, pears, broad beans or courgettes, they do make a contribution.



Garden.ie Members

Not a member yet?
Join now to:

Join Now

Existing Members

Forgotten password

Garden.ie CLUB

Join Ireland's first online garden club! Share pictures of your garden, make new friends and chat with other gardeners. It's simple to join and free! Register Here

Featured Members

a mediateam website

©2018 Garden.ie. Mediateam Ltd, Media House, South County Business Park, Leopardstown, Dublin 18.

Tel (+353 1) 2947777 Email info@garden.ie

Website Design by KCO.ie