Different types of petunias have slightly different blooming habits:

Petunias are "heavy feeders." Because they bloom continuously for months, they deplete soil nutrients quickly.

The duration of petunia blooms depends on several factors, including:

Petunias are one of the longest-blooming annuals available to gardeners. Under optimal conditions, the blooming season for petunias typically lasts from late spring until the first hard frost of late autumn . This translates to a blooming period of approximately 5 to 7 months , depending on the local climate.

While the potential is 5+ months, several factors determine if a plant actually reaches that duration.