Diplotaxis tenuifolia. Sow this remarkable perennial arugula from early spring to late fall for frost-hardy oak-leaf arugula. Dragons Tongue arugula seeds produce plants with arrow-shaped leaves veined with purple on dark green. The leaves are spicy without being bitter. Dragons Tongue arugula grows 30-45cm (12-18″) before bolting. This variety has a very distinctive flavour. Try it in containers or raised beds, or grow it straight out in your organic vegetable garden. Learn when to sow arugula seeds in our How to Grow Arugula instructions in the tab below. We love using Dragons Tongue as baby greens, as the leaves are eye catching and distinctive.