Growing Peanuts in Zone 4?

We have a huge Farmers market in downtown Minneapolis and it is almost always very crowded - every weekend.  There is a huge assortment of vegetables and fruit vendors selling stuff from their farms(and sometimes stuff shipped from another city or even country). Today was my first visit of the year, not so much to buy anything, but to check out what the farmers are selling locally.  Yes, that is my idea of garden planning for next year :)  Also, I end up buying so much stuff than I really should, so that will keep me busy for this coming week!

I use the farmers market as an idea of what other vegetables/fruits I could possibly grow in my own backyard.  If they can grow it, so can I!!  So imagine my surprise, when I found several people selling buckets of peanuts!!  Peanuts, is one thing I had never ever seen in this market before.  I have been going to this market virtually every year for over a dozen years!! 

Unfortunately, I did not have my camera with me, so I couldn't take a picture of the beautiful farmstands.  This is what I bought.

The pile on the left is $2.50 and the right side is $5.  I talked to the vendor and he told me that they save the same raw peanuts and plant them next year.  I have no idea if peanuts will do well in my backyard, but seeing the amount of peanuts they were selling, I'm willing to try.  I plan to save some and eat the rest.  If anyone has any ideas on growing peanuts, please let me know.

Also, these are pictures of the covering for the first light frost last sunday.  Plants were still burned underneath, so maybe I did something wrong....

 

 

Bittergourd(on right) burned under the sheets(: