1846 Apr. 300/2 Each plant should have at least 3 square feet to grow in, as they develop a much larger root-system than those which are grown from tubers.
1946 A. Nelson iii. 21 The tap root and its branches constitute the root system of the plant.
2006 Apr. 13/1 Sweet peas have deep roots and dislike disturbance, so take care when separating the root systems.