I have a bucket and bin system dedicated to just leaves and stems. I throw into the grow room bucket the leaves as is and stems I cut into 2 inch pieces. When I have a bucket filled up, I empty it into the bin and add a couple inches of compost on top. I then put the lid on top. It will start breaking down and heating up. Every 2 months when I harvest EWC, I use this as my base for the new bin. If you were to add all this stuff fresh to a bin, it would heat it up way too much and would hurt the worms, and worms eat the bacteria breaking this stuff down so it needs to break down for a few weeks to be fully available for worms.
I include all my stems, they are almost 1 inch thick! When I harvest my EWC, I simply run everything through a screen. Big chunks and clumps, and stuff that hasn't broken down yet, along with the worms, stays on the screen, and toss this right into my new bin. This brings all the microbes into the new bin, and even the biggest pieces break down after 2-3 EWC runs. Stems are different then nitrogen high leaves, they are more carbon I think, and its fungi that break these down, so its good to include these to get some more fungi action in the bin, IMHO!
Its nice to use 100% of the plant, In this cycle and have no waste leave my house. Glad you asked!