http://articles.extension.org/...
I've only heard of that being done with poppies. Some people sow them on top of snow or surface-sow poppy seeds onto frozen ground (and then hope the birds don't eat it all).
Unless you count 'winter-sowing", where people sow into cut milk jugs or soda bottles and then leave them outside to freeze over.
I never heard either of those being called "frost seeding". But I would like to coin the term "snow sowing".
