Turnip and carrot greens growing in water. They took off after I put water from my dehumidifier in the tray versus tap water. I’m sure rain water would be even better. This is about 3 days of growth. I think you can regrow the greens several times. These you’re basically regrowing for greens. There are recipes out there for vegetable greens.
About day 2 of regrowing my lettuce. It was the butter lettuce that comes with the roots.
My cabbage is starting to grow leaves again. The cabbage just had the cut end. I started it in water and then put it in a small planter that was empty because a plant died. I think any of these could be grown in water.