Loquat purple spot development was studied in the province of Alicante (Spain) during seven consecutive years, and in five commercial orchards differing in harvest time for 2 years. The main environmental factors influencing this disorder were identified.Purple spot incidence showed similar development patterns during the 7 years studied. The highest incidence occurred at the beginning of harvest time, affecting 25-30% of the fruit, followed by a sudden decrease to about 5-10% affected fruit. Early-maturing orchards had higher purple spot incidence at the beginning of harvest time (60%) than late-maturing orchards (<30%), and tended to have higher total purple spot incidence.Low day temperature at fruit colour break was the main environmental factor correlating with annual purple spot incidence, both among years and among selected orchards. Heating plants in a greenhouse during the night greatly reduced incidence of the disorder. Sunshine also affects purple spot occurrence. The amount of affected fruit was significantly reduced, and even nullified, by keeping direct sunlight off the fruit.