When to Deadhead Petunias. Petunias are ready to be deadheaded when faded or wilted flowers have lost their color and appeal.

“Cuticle thickness affects dynamics of volatile emission from petunia flowers,” Nat Chem ... revealed that VOCs can’t diffuse out of flower cells quickly enough to prevent internal damage to the plant ...

PROF. ALEXANDER VAINSTEIN of the Hebrew University of Jerusalem is seen holding a pot of flowers. (photo credit: NATI SHOHAT/FLASH90) Easy-to-grow, sturdy petunia plants produce flowers with a ...