About 30 per cent of Blue Mountains' bees nest in pre-existing cavities, such as rotting wood, abandoned borer holes and hollow stems. As we clear land, for urban development and food production, we remove natural spaces that solitary bees need to nest in. To help replace some of this rapidly disappearing nesting substrate, we can provide nesting spaces for bees.
Bees require three things to thrive; floral resources, chemical free environments and somewhere to rear their offspring. By providing nesting substrate, we are potentially hosting bee nurseries. "Bee Hotels" have become a popular item to purchase. But are prefabricated structures suitable for our little bees?
When creating solitary bee nesting spaces, provide a variety of sizes, to match the diversity of bees. Smaller bees prefer narrow burrows whereas large bees prefer larger burrows. Deep burrows facilitate the production of numerous brood cells within the nest, so drill as deep as a long drill bit, but leave a "blind' end.
When making or even purchasing bee hotels, provide burrows that vary from 3mm to 8mm in diameter. Burrows larger than 10mm tend to attract spiders and small reptiles, which will eat your resident bees.
Bees usually choose natural nesting substrate, holes in dead wood, in trees or limbs. So, to mimic nature, position the bee hotels in full sun. Just as the dead-wood substrate would be in nature. But you should also position the hotel somewhere that you can enjoy the bees activities.