I ruined an entire meal by whizzing a handful of my home grown mint into a dressing. We were astounded by how disgustingly bitter it tasted and the leaves when chewed confirmed it was the mint that was the culprit. It tasted like chemicals and I've got to get rid of the lot. But what could have happened? Does anyone know? The mint earlier on in the spring was fine. It is in a pot, cuttings from last year's mint (I think) and I've been feeding it with seaweed extract every couple of weeks. Any ideas what could have gone wrong?