Technically a wax bean until it develops its purple streaks, this beautiful Dutch heirloom is wonderful to eat fresh, or to save and use as dried beans. When the flat 21ââ¬â25cm (8ââ¬â10ââ¬Â) beans turn from a lime green to yellow with bright purple stripes, they are ready for cooking or freezing.àDragon Tongue bush bean seeds…