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

Other days

buddy

Buddy Day
hoodie

Hoodie Day
get funky

Get Funky Day
singles

Singles Day
book

Book Day
eat what you want

Eat What You Want Day
cuddle up

Cuddle Up Day
slime

Slime Day
youth

Youth Day
hiv awareness

Hiv Awareness Day