A little plea for diversity: would the people who have been planting clumps of garden bluebells in the woods on Dublin's Killiney Hill please stop? I'm sure these phantom planters have entirely good intentions in rehoming their surplus bulbs, but their actions are harming our native bluebell population.
You see, these garden transplants are the Spanish bluebell (Hyacinthoides hispanica), a much heftier and hardier species than our indigenous bulb. The two cross readily, giving rise to a mongrel bluebell. And as these mongrels and their Spanish parents are more robust than the natives, the local population is in danger of being seriously diluted by foreign blood, if not muscled out altogether in some areas.
The Irish bluebell, which is actually known as the "English" bluebell (although it is native throughout western Europe, from central Spain up to the Netherlands) is a wispy-looking thing, with cream-stamened, rich-blue flowers dangling romantically from one side of an arching stem. Its "Spanish" cousin (indigenous to southwestern Europe and northern Africa) has little of the grace of its more northerly relation, being paler and fatter, with flowers sprouting from all sides of a more upright stem.
I have to address the other bluebell-moving people here: those who remove the native species from the wild. Please leave them there: don't dig up the bulbs, and don't pick the flowers, either, for that matter, as they provide the seeds for future generations of the plant. An entirely legal and trouble-free way of getting the native Hyacinthoides non-scripta into your garden is simply to buy it. Both Mr Middleton and Wild About Bulbs sell the bulbs in bulk (at less than €30 for 100). No sneaky digging, no subterfuge: you pays your money and you gets your bulbs - all legally grown and harvested.