In cooler climates, red onions need to be planted in warm, moist soil immediately after the last frost. These spring-planted onions will be ready for harvest at the close of summer. In mild climates, red onions can also be planted in fall for a spring harvest.
About this Author
Living in Southern California, Shayne Ochoa has been writing professionally since 2005. Her articles have included topics on education, child development and gardening. She also holds a Bachelor of Arts degree in liberal studies from California Baptist University in Riverside.