Carl Sprengel

Karl or Philipp Carl Sprengel (March 29, 1787 – April 19, 1859) was a German botanist from Schillerslage (now part of Burgdorf, Hanover).

He travelled the world between 1810 and 1820, exploring agricultural ideas in Asia, Americas and Mesopotamia.

In the early 1830s, he moved to Regenwalde (Resko), where he accepted position of the Chairman of the Pomorskie Towarzystwo Ekonomiczne (Pomeranian Economic Society), which he held for the rest of his life.

Having his financial needs satisfied, finally he could fulfil his dream and establish Regenwalde Akademie der Landwirtschaft (Academy of Agriculture in Resko),[2] where he taught, studied and lived until his death in 1859.

Influenced by (one of the students at Regenwalde Akademie der Landwirtschaft) Felicjan Sypniewski theories, Sprengel was the first to formulate the "theory of minimum" in agricultural chemistry, meaning that plant growth is limited by the essential nutrient at the lowest concentration.