June sees the arrival of some fascinating bees in the garden – The leaf-cutter bees (Megachile spp). Well, they’ve been in the garden since last summer, just hunkered down in safe, leaf lined cells in tubes, hollow stems and bee houses.
You might not notice the bees to start with. They start to hatch out in late May and early June, and like most solitary bees, it’s the males at the front of the nest that emerge first. They disperse a bit and feed on nectar rich flowers, biding their time, waiting for the females to hatch.
The first signs that you have leaf cutter bees in the garden are little semi-circular notches cut out of your foliage. Roses are a favourite, but many other shrubs are used including wisteria. Some have been known to use flower petals too. Take a look at your bee house and if the tubes are sealed with leaves you have leaf cutter bees in residence.
The female leaf cutter bees stand on the edge of the leaf and cut around their body shape, flying off with a neatly cut piece of leaf that they use to line their nest. Piece by piece the female creates mini cigar like packages, one for each of the eggs that she lays. Inside she provisions each one with a ball of pollen wetted with nectar, before she lays one egg and seals it up.
There are eight species of leaf cutter bee in the UK and there are about four that you may well find in your garden. The males supp on nectar, but the females collect pollen beneath their abdomen on a feathery brush called a scopa.
Leaf cutter bees do not eat the leaves of your plants and they are not garden pests. Plants that have had the Leaf-cutter bee treatment are not harmed or
injured in any way and there is no need to worry about them. Never, ever try and
control them or treat them as a pest, they are an absolute joy and are much better
pollinators for your garden than honeybees. Plants affected will simply grow more
leaves in due course. In fact it is a real pleasure to see the notches around the garden
because it means these exceptional creatures are alive and well. The Leaf cutter bees
are excellent pollinators. This is because they are messy little bees and manage to get completely covered in pollen as they forage for food. They have a hairy underbelly
designed to trap the pollen and as they move from flower to flower they transport the
pollen grains to the female flower parts and pollination occurs.