I take my rolling garden cart to sit on in my front yard every winter and pick gallons of chickweed; just the top 3-4 inches where the stem is still rather tender. I carry a plastic grocery bag and fill it several times then rinse the weed and saute it in olive oil with a bit of salt. After it's cooled I freeze small portions of it by wrapping them in plastic wrap then laying them on a sheet pan to freeze and put all the frozen packs in a freezer zipbag. I have chickweed throughout the summer. It is very similar to spinach when cooked. I also like to cut it up with scissors and add to scrambled eggs.
RennieB