Giant seaweed is harvested from seaweed patches. 23 farming is required to plant the seaweed spores and harvest the finished plant. Planting results in 19 experience while harvest yields 21.
A minimum of 3 giant seaweed will be harvested from a plot. With super or ultra compost, each harvest will average 15-32.
The magic secateurs does not increase the yield of giant seaweed.