Arugula Seeds Heirloom Herb. Strong tasting, spinach-like greens with delicious nut-like flavour that are quite popular in salads or cooked like spinach. We recommend picking young shoots when 5-15 cm (2-6″) long for best fresh salad flavour while the older foliage makes an interesting steamed vegetable. Generally the first shoots can be harvested from plants about 30 days after germination. If you only remove younger shoots from main stem, plants will continue to offer foliage until blooming. It is interesting to note that plants vary in leaf shape and earliness of flowering and as with many greens, a cool season is best for this plant. Plants can mature to 90 cm (3′) tall. Arugula is also known as Roquette or Rocketsalad. Annual.