Last night we made a green pea soup and apart from the Hablitzia (Caucasian spinach / stjernemelde), I used perennial vegetables growing in a wild part of the garden. With little or no help from me there’s a bounty of wild edibles in this area under wild hazels (Corylus avellana) and this made for a delicious pea soup with masses of greens. 
Campanula latifolia is documented as used in spring soups in the 16th century in my area in Norway and Heracleum shoots are also a tradional soup ingredient, in particular Russian borsch now thought of as a beetroot soup was originally made with hogweed shoots.