If at all possible, don’t buy mums in August. If you can wait until mid to late September (2^nd or 3rd week), that would be best because then they will last through October and into early November. Buy tightly furled buds. Know that petal pigments FADE more in full sun. Light-colored fade faster that the dark-colored petals. The darker petals provide a brighter display for the longest time. Mums fade after a good heavy rain, however, they really need to be watered every day or at the least every other day.