Rex Begonia, the king of begonias is at number one position in the list of house plants as its velvety leaves, color and natural marking on the leaves is just amazing. The silvery hue appears pink or green in different light. Begonia needs filtered sunlight in plenty to grow. Also the optimum temperature for the growth is 18° to 23°C. Begonia also requires moist and fresh air. Do not keep them wet as very susceptible to rot also fertilize occasionally through summer and spring.