In late summer the nests of most species begin to produce males and new queens. Until this stage the queen won’t have laid any eggs that hatch into males. As their only role is to mate with the new queens from other nests, the males leave the nest and cannot return. Their days and nights are spent outdoors, mostly clinging to flowers, cruising hedgerows, or, in the case of Tree bumblebees, hovering around outside the nest looking for queens with which to mate.
Producing new queens and males takes a lot of energy, and nests can only do it when they reach a large size, with a good store of food. If a nest doesn’t produce males or new queens, it has ultimately failed. It is crucial that the nest has a good supply of food for the new queens and males. This is where you can help, by providing a good variety of bee-friendly flowers to feed on, right up until the autumn.
Try planting Cosmos, Honeysuckle, Sedum or Cornflower which can flower well into September. Or if you want to try and plant this month, give oregano, sea holly or columbine a go!
You can download the bumblebee menus HERE for inspiration.
Information from the Bumblebee Conservation Trust: https://www.bumblebeeconservation.org/