(60 days) Open-pollinated perennial, Zone 4, native to Europe. Start seeds indoors and transplant to cold frame, keeping watered, or direct sow in soggy stream bank. Also good in pots. Likes sunshine. Keep picked; it gets bitter once flowers form. Its peppery taste enhances many a salad, soup and tea. Super-nutritious, it has more vitamin C than an orange (was long a treatment for scurvy), more calcium than milk and more iron than spinach. According to University of Connecticut researchers, contains a compound that inhibits numerous types of cancers. Since ancient China and Egypt, has had widespread culinary and medicinal uses. It is also a candidate for possible use in phyto-remediation or wastewater treatment operations.
It is potentially invasive: we cannot ship to Connecticut or Illinois where it is banned. In other warm moist locations, keep a close eye on plantings to prevent its unwanted spread. Its many uses perfectly illustrate the conundrum posed by potentially invasive plants: how do we find ways to control them and harness their many benefits instead of banning them? ④