Just thought I'd share my revelation with everyone around here! I always get cases of lettuce trimmings and other greens from local veggie shops and grocers. Lots of broccoli and cauliflower leaves, arugula, chicory and more. I used to just make big piles on the ground in summer, but now it's winter (southern hemisphere) and the ground is pretty muddy and once the greens get too muddy they no longer eat them. So I made a feeder that works beautifully! I ordered some mesh online, like the kind for hockey and soccer nets, and I put the lettuce in there and made a drawstring rope. Super easy! It works beautifully and the chickens LOVE that they can pull off little bits. I hang the whole thing just above the ground, but I put a rock between it and the ground so that it doesn't swing too much. Usually there's very little waste, although the batch I had just before this had lots of thin chicory leaves that just pulled right out so there's lots of those on the ground.
