When Charles and Francis Darwin first documented phototropism,why was it important that they germinated the grass seeds in the dark before beginning the experiment?

Question

Quizplus · Accepted Answer

Germinating the grass seeds in the dark ensured that the young shoots grew straight, rather than bending towards any existing light source. This standardizes the starting point of the experiment and allows for accurate observations and measurements of phototropism.

When Charles and Francis Darwin First Documented Phototropism,why Was It