I've tried a plant called American Land Cress - have you tried that? Theoretically, watercress grows in running water, and is in my view, nicer. It's peppery in flavour, and full of vitamin C. (Also, if wild, possible liver fluke and assorted other nasties.) England used to have many watercress beds where there was abundant spring water to be diverted into gravel channels, and bunches would be sold in the street in London. Imagine Liza Doolittle crying out about the stuff instead of vilets.

We used to have a song in radio music lessons which went as in here,

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Penny