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Fastest-growing seaweed

Fastest-growing seaweed
Who
Macrocystis pyrifera, Giant sea kelp
What
0.000021 kilometre(s) per hour
Where
Not Applicable
When
Not applicable

With a growth speed of up to 0.5 m (1 ft 7.6 in) per day, or 0.000021 km/h (0.000013 mph) as its fronds approach the surface, the giant kelp (Macrocystis pyrifera) found off rocky shores in the Pacific Ocean is the world’s fastest-growing marine plant.

It is also the fastest-growing marine plant overall an the longest seaweed, reaching as much as 60 m (197 ft) long.