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

Other days

kiss a brunette

Kiss A Brunette Day
artists

Artists Day
boba

Boba Day
nail polish

Nail Polish Day
china

China Day
tulip

Tulip Day
kiss a ginger

Kiss A Ginger Day
bow tie

Bow Tie Day
boy friend

Boy Friend Day
lash

Lash Day