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

Other days

kale

Kale Day
pumpkin

Pumpkin Day
blanket fort

Blanket Fort Day
kiss a ginger

Kiss A Ginger Day
my little pony

My Little Pony Day
one

One Day
tulip

Tulip Day
first love

First Love Day
me

Me Day
ponytail

Ponytail Day