Bumble bees do not collect their own nesting materials, therefore look for nesting sites pre-fitted with materials. While your Bumble Bee Nesting Box will come complete with the desired nesting material, there are other options available which have proven successful nationwide.
Experimenting with materials such as dry moss, straw and/or upholstery wadding. Where possible, steer clear from cotton wool as the small barbs on the bumble bees’ legs can sometimes get tangled. A bit of dried grass is also a great option, though the nesting material that comes complete with your nesting box is true, tried and tested and has provided reasonable success in all parts of the country.