Observations during field trials suggested that high temper atures at planting time were associated with reduced calendula stand establishment. A germination study by Harrington (1921)concluded that at constant temperature calendula germination reached a maximum (65%) between 15 and 25◦C within 6 d. Germi-nation of the medicinal cultivar ‘Bonina Sortida’ was rapid, reachingnear maximum germination levels within one week in incubators