Encourage further blooming by pruning your pansies.
image by Paige Foster: sxc.hu
Pansies require pruning or "deadheading" to remove the spent blooms before they go to seed, which helps the plants produce flowers through the summer and late into autumn. Deadheading is also used to trim the plants when they become leggy. During the height of flowering, prune your pansies at least every two weeks.
Look over each flower stalk for blooms that have faded or are beginning to fade. Look for seed heads that may have already formed.
Using your thumb and forefinger, grasp the stem of the spent flower 1/4 inch above the nearest leaf set. Pinch off the flower head.
Pinch back stems that are longer than the bulk of the plant. Pinch the stems directly above the leaf set nearest to the height to which you wish to prune the pansies.
Prune the entire plant if it has become unkempt. Trim each stem to approximately 4 to 6 inches long using shears. Pinch 1/4 inch above the nearest leaf set to this height.