He grew a willow tree for five years in a pot containing 200 pounds of oven - dry soil .
Jan Baptist van Helmont published what is considered the first quantitative experiment in plant physiology in 1648 .
Jan Baptist van Helmont grew a willow tree for five years in a pot containing 200 pounds of oven - dry soil .
Jan Baptist van Helmont published what is considered the first quantitative experiment in plant physiology in 1648 .