Source: Post-Ring War
Disclaimer: Tolkien knew these woods.
“Ave youm seen ‘em?” The old hobbit demanded of the Master of the Hall.
They lay beyond the Buckland Road, spreading out from the trees that edged the Old Forest. Among the meagre, scattered white bell-flowers, patches of blue ones had appeared. Only a few last year, but this spring there were huge swathes. Folk scratched their heads, but after all them rum things had happened down south... well, ‘twas another curiosity.
Merry wanted them called ‘Bombadil’s Beauties’; there was a strong following for ‘Elf Caps’, but in true hobbit fashion, they became known as what they were – Blue Bells.