Edible green roof plants - part 2

Last year I blogged about edible green roof plants, little used plants which could perform well on a roof, while potentially filling our stomachs.
I continue to read everything that I can get my hands on, looking for other overlooked gems.
Here are a couple more to add to the list, generally considered to be weeds but with a shift in perspective, I think they could be helpful as accent plants. And if you see them up there, maybe leave them...they could come in handy.

Purslane 

Also known as Pigweed, Little Hogweed and at least three other names, can do well in lots of soils, including poor ones and is fairly resistant to drought. It has a taproot, but is not aggressive from what I have seen and because of its spreading ability it creates humid microclimates for other plants to exploit. It spreads easily (via thousands of seeds), maybe too easily, but has a decent taste. Personally I think it’s better raw than cooked.  A special feature, it has more omega-3-fatty acids than any other leafy vegetable and a ton of vitamins.

Violet

A great companion plant for shady areas, one of the few I can think of. It can be used for salads, desserts and more, especially good when candied! Because there are so many species around the world, it can be used almost anywhere, including very cold climates.

Broad-leaf Plantain

Huge, huge asterisk here. Although it could be used, in theory, as a companion plant, I wouldn’t put the most common varieties in on purpose. But I might leave them in if they were already there. The reason? This plant is REALLY hard to get rid of. And I don’t think the most common varieties look good next to most of the sedum species plants usually used. It’s an uncomplementary companion plant, if you will. Nevertheless, it can has both medicinal and edible attributes and if you can get your hands on some ornamental cultivars, you’re in for an aesthetic treat.