Success in blooming pansies and violas in the winter season depends on two key factors: date of fall planting and soil nutrition. If you live in USDA plant zone 6, pansies must be planted by October 15th, two weeks earlier in northerly zone 5, or two weeks later in zone 7. Early fall planting promotes faster and deeper rooting of plants before the cold weather arrives.
Pansies need feeding bi-monthly with 10-10-10 or equivalent fertilizer to achieve maximum bloom potential. Either organic-based or slow release fertilizers are good nutrition sources.
Other pansy ideas:
Offer plants a weekly drink of water if rainfall in your gardening area is low.
In the fall consider interplanting tulip or hyacinth bulbs among the pansies or violas.
Warm weather in mid-May will stretch pansies plants and look "worn out". It is time to plant summer annuals. Remove pansies and add them to the compost pile. Add finished compost to the flower bed before digging in summer annuals.