Two harbors were originally constructed and were named
Mulberry A and Mulberry B. The harbor at Arromanches was
Mulberry B, while Mulberry A was near Omaha Beach where
the American forces landed. Unfortunately, just a few days
after the harbors were built, a major storm struck.
The harbor at Mulberry A was completely destroyed, and
Mulberry B was severely damaged. After the storm, all of
the Allies had to use the harbor at Arromanches.

the harbors were named "Mulberry"
because the mulberry plant grows so fast!