I am a lover of cooking with common wild weeds. Dandelion, nettle, mallow, purslane and lamb's quarters find their way to the table while other common weeds like burdock, yellow dock, motherwort, and mullein are used more as medicine than food.
Lamb's quarters, Chenopodium album, are my favorite mild green, I like them way better than spinach. They are abundant, tender, and tasty -- a typical case of an under-appreciated plant. They are best harvested before the plant blooms but if you're pinching off the tops all along, you delay that process. Use them the same way you would use spinach.
Here's how I blanched and froze my first batch of wild greens this summer.
I gathered a big bowl of lamb's quarter tops with tender leaves and stems. Greens need to be blanched before freezing so I brought about 1½ gallons of water to a boil, added the greens, set the timer immediately for two minutes, and brought it back to a boil. Since I'm at a high altitude, I gave it another half minute. When the time was up, I spooned the greens with a slotted spoon into a big bowl of ice water to stop the cooking process -- for about another two minutes. (I saved the cooking water to cool down for watering potted plants.) Then I placed the greens onto a big terry-cloth towel spread out on the counter and rolled them up for a minute. After measuring out 2-cup quantities, I chopped them a few times on the cutting board and bagged them.
A trick to get all the air out of the freezer bag is to stick a straw in the bag and suck as you close the bag. It really works. These smaller bags were placed into another larger freezer bag, making them double-bagged. I've never had any freezer burn problems with this method.
Twelve ounces of greens (by weight) turned into two 2-cup packets for the freezer. It was less than a half hour of quite pleasant work. If I do this five more times, I'll meet my gardening goal of 12 packets in the freezer!