A nice idea to encase the Advent wreath with knitted or crocheted wool ;-)
Links:
Knitted Advent Wreath (“Der Liesl” – Adventskranz im Strickkleid) (German)
Google translation of the article
If you want to know more about Advent wreaths in Germany and perhaps even want to make one yourself, check out Christmas Craft Projects – Advent Wreath and How to Make Natural Green Wreaths on the same site.