Pinching an ivy geranium encourages branching, which makes the plant full. The more branching, the more flowers the plant will have.
Starting early in the season, pinching involves removing the tip of each branch. It can be done about once every three or four weeks until the weather gets hot---about mid-June for most gardeners. Flower buds will soon develop.
Deadheading, another type of pinching, encourages new buds to form in place of spent ones. It consists of simply pinching, snapping off, or pruning each flower stem after its flower fades.