Hi ngp
Virescit is latin and it means "rinverdisce", something like "It grows green, it grows up again".
Here's what I found googling:
It comes from a latin expression, quoted by Nietzsche: "increscunt animi, virescit volnere virtus" (gli animi prendono vigore, il valore rinverdisce dalla ferita) = Free translation: Souls get strong, bravery turns green again thanks to the wounds.
Before the final battle, ancients used to cry this out loud.
But let's wait for other opinions...
Ciao!

Walnut