I really like Lamb's Quarter
, maybe cause it's a bit of an underdog on this side of the world. It is considered a weed in Canada and the US, which is crazy as it's highly nutritious, grows everywhere and tastes like spinach. Plus apparently you can eat the seeds like quinoa... which I haven't tried yet.
Check this out
, in just one cup 46% DV calcium, 5.8g protein!!! Plus lots of other minerals and vitamins. I just planted some on my patio.
Now these percentages are based on steaming the greens, and I suspect that's where you're getting the high percentage of calcium. Similar to spinach the calcium content increases after lightly cooking (thanks for the tip Mom).
Don't weed and trash, weed and eat!