Daft in modern English means silly, foolish or mad, but here it has an older sense — which survives in Scots — of somebody who is thoughtless or giddy in their mirth, so daft-days is an exact translation of the French fêtes de fou.
~World Wide Words
Daft Days are the period of celebration between Christmas and Hogmanay (New Year's) or Twelfth Night (January 5). "A Toast Tae The Daft Days":
Addendum: Just realized I should have said that she wrote this poem (poyum) herself! She is Len Pennie.
Michelle Kogan has the Poetry Friday round-up. Thanks, Michelle!