Oops, it doesn't look like 'stem stem day' is a national day..

Other days

ormille

Ormille Day
promposal

Promposal Day
tulip

Tulip Day
self care

Self Care Day
cursing

Cursing Day
pick me

Pick Me Day
prosecco

Prosecco Day
pampering

Pampering Day
cuddle up

Cuddle Up Day
fiancee

Fiancee Day