"how" expounded:

Actually it is called fasciation or your spell checker is on automatic and
changed it ;-) I've only seen it happen in water lilies.

I usually have one or two foxgloves out there showing signs of
fasciation. Sometimes the flower scapes are two inches wide by
one-quarter inch thick, with rows of flowers in stripes up and down
the scapes. Very strange looking.
--
Ann, Gardening in zone 6a
Just south of Boston, MA
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