Building insect homes
Insects will use man-made structures in which to lay eggs, or to hibernate in through the winter either as an adult or larvae. These range from woodpiles, garden canes and furniture to holes in brickwork and garden sheds.
Making an artificial chamber
Artificial chambers help serve this purpose. Some use natural materials, while other make use of recycled household items. Here are a few ideas:
- Cut the bottom from a 1 or 2 litre, plastic drink bottle and place inside it a 100cm (3ft) rolled length of corrugated paper. Use a thin piece of wire, pushed through both side of the bottles base to hold the card in the bottle. Keep the lid in the bottle to prevent any rain getting in, then hang the bottle among the densest foliage in trees, bushes and garden fences, particularly near lights, in mid-August.
- Bundles of tubes are also very successful in providing somewhere for insects to lay eggs or to hibernate in. The hollow stems of bamboo or hogweed are an ideal natural resource. Gather tubes into a bundle and secure together with string or wire. Ensure one end is blocked off so the tubes do not become a wind tunnel. A catering sized coffee tin can hold your straws and tubes. This also ensures that wind does not pass straight through. Alternatively, use a log with lots of small holes drilled in.
- Hang tubes and boxes in a tree or shrub, or fixed against a wall where it is warm but not too hot. It is best to put them in place before the spring, ready for when bees emerge. Tilt the front slightly when hanging it, so water can drain out.
- Some styles of ready-made bug boxes combine homes for ladybirds, lacewings and solitary bees with narrow, vertical roosting and hibernating slots for butterflies. Some for ladybirds, have a louvered front, behind which is a honeycomb of insulating material in which the ladybirds can shelter.
- Bumble bee boxes and pots are somewhat less successful and it is possible there are sufficient natural nest sites available them. When purchasing a ready-made box, ensure it is made from sustainable sources and is FSC accredited.
Natural features for insects
- Retain natural features for beneficial insects. Dead stems are good for over wintering adults or larvae. The hollow stems of herbaceous plants, or shrubs such as elder or buddleia are particularly useful.
- Retain dead vegetation, leaf litter and log piles. They will be used as hibernating and breeding sites, particularly by ladybirds.
- As long as there is no structural risk, small holes in the mortar between bricks offer useful places for insects to hibernate or breed. If you have to carryout any re-pointing, look for opportunities to retain holes.
- Solitary bees and wasps like to burrow into dry sunny banks or warm patches of bare earth in a lawn or border, even among a pile of stone. Look to retain such features. If you have a south-facing embankment keep a proportion of it free of dense vegetation to provide opportunities for nesting.
- Ladybird larvae are commercially available as a natural form pest control. However, many are of non-native foreign species, which can predate and or out compete with our own native ladybirds. Therefore, it is best to avoid these, as there is no way of telling the provenance of what you have brought.