Castor is a tropical crop that needs moderately high temperatures (20–27°C) with low humidity throughout the season, and grows best with clear, warm, sunny days. Prolonged cloudy weather with high temperature at flowering gives poor seed setting (known as sex reversion).
Pending expert review
Source
Crop Production Guide – Agriculture 2020 (Directorate of Agriculture, Tamil Nadu & Tamil Nadu Agricultural University (TNAU)), Castor – Climate requirement, p. 206
