The brilliance of fall leaves depend greatly on weather conditions that occur before and during the time chlorophyll begins to dwindle within the leaves. Temperature and moisture are the two most significant factors in leaf change color over the course of fall but the shortening of days also triggers this natural effect. When you have warm, sunny and cool, crisp nights without freezing the season will bring the most spectacular color displays.

The cool nights and warm days coax sugars, produced in the leaves, to move through the veins of the leaf. Cold weather however closes these veins, preventing the sugars from moving. The movement of the sugar and lots of light increases production of anthocyanin pigments which tints the leaves reds and purples.

The amount of moisture in the soil also effects the color produced by leaves in the fall. Soil moisture varies greatly from year to year and all of these factors make for no two autumn seasons being alike. If Massachusetts has a warm, wet spring, fantastic summer weather and a warm fall, the leaf color will be more brilliant then a late spring, hot, wet summer and cold fall. Too many factors play into leaf color.