Total cost for this project was $0, love that. I had been looking at purchasing the coir / coconut liners for the hanging baskets but they were between $8 and $16 each, so I figure this is a good savings.
To felt the wool I put the sweater in my kitchen sink with hot water and just a splash of dish soap. Then I picked up the sweater and threw it down as hard as I could to get the fibers to start to tighten up. I did this until my arms were tired then I carried the sopping wet mess to the washing machine and threw it in there with a few kitchen towels for balance.
I ran the beginning part of the wash cycle 3 times to really agitate the wool and tighten the fibers. This also loosens up quite a bit of bits and pieces. I took a small colander and skimmed those floating fibers out of the washing machine so I didn't end up clogging the plumbing and having a zero dollar project turn into a huge repair bill :)
I then let the sweater finish the cycle and dried it on high heat. The wool had felted beautifully! Then I just grabbed my Fiskars pinking shears, my upholstery needle and black embroidery thread and sewed the liners to the baskets.
Felted wool is very forgiving and I actually couldn't see much of what I was doing because I was in a semi-dark living room watching a movie with the family while I was doing this, but you really can't tell in the finished product! So this is a very easy, cheap and forgiving project to do on your own.
Here's what my baskets looked like before (oh, I also spray painted them with some white crackle paint I had leftover, but I did that months ago and had been wondering how to line them.)
And here's the finished products! I've got a set of three with black and cream liners that will go well in my new garden I'm building for my daughter!
I plan to fill them with pink wave petunias and strawberries.
When I fill them with dirt they will push up against the wire and look a little more full, which will be great!