Yes white flowered Bluebells do occur but more often what is thought to be a white Bluebell is actually yet another wild garlic, the Three Cornered leek. In the two following photographs the first, taken in Fairlight Glen shows the Three Cornered Leek alongside a Bluebell and the second, taken on the Firehills shows both white and blue Bluebells. Look closely and you will see a subtle difference in the flowers. An easier way to be sure of which plant you are looking at is to inspect the stem because the Three cornered Leek gets its name from it’s three cornered stem whilst the Bluebell has a round stem. Both are members of the Lily family.