Pumpkin

Gives

Each item has its own chance per use. Quantity is the count before any yield bonus.

Item	Quantity	Chance per Use
Pumpkin	Quantity 1	Chance per Use 100%

At your selected Herbalism level 1, each item has a 0.15% chance to yield one extra. The extra-item chance ranges from 0.15% at level 1 to 45% at level 300. ?How gathering works