Here is another idea, I have used duct tape to cover the tear. Then I sew the edges of the duct tape to the blanket. This helps the tape stay in place and the duct tape helps keep the water out. It needs to be warm and dry when applying the duct tape, so I recommend bringing the blanket inside.
thanks for the tips, i already knew that dental floss was strong but i didn't think to use it on blankets. I've used it to repair leather like my riding boots.
For those of you in the Rochester, NY area - check out The Stitchin Post - she does a really good job on blankets - she washes and repairs them - my mare is great at ripping them. Call her 585-303-1542
I also have rolls of "Duck Tape" around, to patch up rips when I can't get proper repairs. I put a layer of tape on the inside of the rip and the outside. It lasts quite well until real repairs can be made.
Im so lucky my mare is very careful with her blanket! Hasn't ripped or damaged it at all, and she is out 24/7 Great article, will keep in mind if she ever does rip it.