Often overlooked in urban landscapes, insects and other invertebrates are vital for our green spaces—they’re the invisible workers who pollinate plants, feed animals, and clean up whatever’s left. However, our bugs are under threat as the green spaces which provide them with food and shelter are engulfed by growing cities. To protect our beasties—and the viability of our parks, gardens, and farms—we need to fill part of the gap that's left when their habitat is ruined.
Planting pollinator-friendly plants, as carried out locally by Edinburgh Student Housing Co-operative and Greening Our Street, is a popular solution to feed some species, but doesn’t address the whole problem. While most of us appreciate the flowers that support many insects, the dead wood and leaf litter which other animals rely on is less charismatic. The sad fact is that what many of us consider unsightly green waste is a haven for our wildlife.
One solution is to designate areas of suitable habitat to support local invertebrates. This can be as simple as letting grass grow a bit longer, or as elaborate as the beautifully designed 'bug hotels’ used in some gardens. Bug hotels are man-made structures which copy the natural habitat of insects and other invertebrates. They normally use natural materials but are neater and less likely to be disturbed by passersby than wild habitats. They can easily be created from recycled kitchen or garden waste, and make wonderful projects for children and adults of all ages.
Making a bug hotel has two main steps: first you make or find a hollow structure, then you fill it with some kind of bug bedding. The structure and its filling can be varied to target different invertebrates depending on where you are, what’s endangered in your area, and who you want buzzing, crawling, or sliding round your garden.
For the structure, you want anything which will hold your filling in place, not fill with rainwater, and allow bugs in and out. Stacks of old shipping pallets or wooden boxes make fantastic frames for bug hotels, and can provide a huge variety of habitats in a small area. Flowerpots make a great base for smaller hotels, and can even be left upside-down and unfilled to house bumblebees. Plastic drinks bottles or tin cans can also be a simple way to start, though make sure they’re placed or cut in a way that lets rainwater drain away. Cardboard boxes can also make a good temporary solution, particularly under shelter or in drier weather. The type of structure you choose can limit the size and placement of your habitat, all of which helps select the species you’ll find inside it.
The filling of your hotel is what mostly decides who comes to stay, your goal is to provide something similar to their natural habitat. Wood is a great material as there are many species of beetle and fungi who depend on it, but it is routinely cleared from almost all urban areas. Small holes (2–8 mm) can also be drilled into, but not through, the wood to provide burrows for solitary bees, who pollinate many of our plants but can’t live in hives like their famous cousins. Bundles of bamboo or reeds can also work for solitary bees and other burrowers, keep an eye out for plugs of mud or leaves over the holes as this means your hotel has some residents. Dead leaves, including straw and hay, offer burrowing and feeding opportunities for hundreds of species, including butterflies and aphid-controlling ladybirds. Bark, egg boxes, and cardboard also make useful habitat for many species, particularly lacewings, which eat loads of common pests.
Hotels are best placed near flowerbeds and other food sources, and in warm parts of the garden, such as south-facing walls. A simple way to start out is with bamboo or reeds tied or stuffed in a can or cut bottle and hung from tree, or a drinks bottle full of dead grass, leaves, and twigs. Either of these can really help support your local bugs, and keep our urban green spaces healthy.
