Keep chemicals, oils, antifreeze etc. in leak-proof containers out of the reach of any hedgehog that might wander in. Antifreeze is especially hazardous as its sweet smell attracts hedgehogs but is lethal if ingested.
If shed doors have been left open for some weeks, be sure to check for nesting hedgehogs before closing the doors. Hedgehogs may also try to nest underneath sheds, so take particular care if you decide to dismantle your shed; we suggest dismantling in October after hoglets have left the nest but before hibernation season.