Spanish Bluebell, Hyacinthoides hispanica, is the bluebell of gardens. It has flowers all around the flower stalk, including some facing upward. The flowers are broad-mouthed and open wide. They are a lighter shade of blue with (usually) blue anthers (see Bluebell - 7th May). The leaves are much broader too.
It hybridises easily with our native Hyacinthoides non-scripta to form intermediate forms known as Hyacinthoides x massartiana. Unfortunately the seed produced by the non-natives is bountiful and fertile so the plants rapidly invade native populations. This has lead to them being considered invasive species and the natives as being under threat.
This second post today is to catch up for not posting yesterday; I didn't get back from work until after midnight!