Karengo Closely related to Japanese nori and Welsh laver, the red seaweed karengo (Porphyra species) is a delicacy to Māori. Found growing on intertidal rocks on exposed coasts, karengo is picked and sun-dried in winter months. It keeps for a long time in a dry condition. When used in cooking the dried seaweed is steamed or simmered for 30 minutes. Karengo is harvested from the Kaikoura Coastline in August and September and is common on the upper intertidal zone. A highly edible seaweed.