Lesson 4
Nesting sites and hibernation shelter
Pollinators do not just visit — they live with you, if you let them. Solitary bees nest in hollow stems, beetle holes in dead wood, bare soil tunnels, and crumbling mortar. Bumblebees nest in abandoned mouse holes, under sheds, in tussocky grass. Hoverflies pupate in compost. Ladybirds hibernate in leaf litter and under bark. If your garden is tidy — lawn mown to the edge, beds mulched with bark, hedges clipped tight, no dead wood — there is nowhere for anything to breed or shelter. You get visitors in summer, but no residents.
The simplest beneficial infrastructure is a log pile in a shady corner, left for five years. Drill holes 8–12 cm deep and 2–10 mm wide into the cut ends if you want to accelerate occupancy. Stack hollow stems — bamboo, raspberry canes, elder — in bundles and tuck them under eaves or in hedges. Leave a patch of bare, south-facing soil undisturbed from March to September for ground-nesting solitary bees. Do not mulch it. Do not weed it.
Bumblebees are harder to accommodate deliberately, but you can tilt the odds. Let grass grow long in a corner from April onwards. Leave an old upturned flowerpot half-buried with a 2 cm entrance hole. Do not disturb it. Bumblebee nests fail if flooded, so good drainage matters. Some species nest above ground in dense evergreen shrubs or old bird boxes stuffed with moss. You cannot force it, but if you provide options, one queen will find you.
Quick nesting infrastructure
- Drill 8–12 cm holes in logs (2–10 mm diameter range)
- Bundle hollow stems 15–25 cm long, tie with string, hang under eaves
- Leave one bare soil patch 1 m × 1 m, south-facing, undisturbed Apr–Sept
- Stack logs in shade, leave 5 years minimum before moving
- Let ivy grow thick on a north wall — winter shelter for ladybirds
Building a simple bee hotel
- 1.Take a wooden box 15 cm deep (an old wine crate works).
- 2.Fill with bamboo canes or drilled logs, all cut to the same 12 cm depth.
- 3.Drill holes 2, 4, 6, 8, 10 mm wide — different bees need different diameters.
- 4.Ensure all holes are smooth inside (sand any splinters).
- 5.Mount 1–1.5 metres high, facing south or southeast, sheltered from rain.
- 6.Leave in place year-round — bees overwinter as larvae inside the tubes.
Bamboo canes are fine, but make sure the internal nodes are pierced — bees cannot drill through them.