If you are planting in containers, you should always make sure the plants are fertilized. Potting soil does not always contain nutrients, and nutrients may have washed through older containers. If you are planting in the ground, plants don't usually need extra fertilizer. However, not all soils are naturally fertile, so adding a balanced fertilizer can be helpful.

Pansies are quite cold tolerant, and can bounce back from overnight, single-digit temperatures. Nonetheless, very cold weather can leave vegetation looking sad. In the southern states pansies are one of several winter annuals that tend to stay low to the ground over winter, and bloom from late winter through spring. When plants begin to put out new growth you can pinch back the most damaged vegetation.

Plant winter hardy annuals in October to make sure they get settled in before really cold weather arrives. Potted plants will do better in larger containers, because the greater volume of soil doesn't get cold as quickly as a smaller container.

I just had been thinking that fertilizing in winter would cause them to have tender growth that would be killed by cold but so far it looks like they can handle it.

Fertilizing in winter can induce new growth, IF you use something like Miracle Gro. Liquid fertilizer enters the plant through both the leaves and the roots. But, time-release fertilizer can take 8-9 months to finish releasing and also requires 70ºF soil temperature. Your plants benefited back in the fall, but they are not getting enough fertilizer now to stimulate new growth.

We've had near 70 degree weather in January this year though I guess the soil was not that warm. Whatever, they look like they've grown.

Took a look at them awhile ago. Most of them are blooming and they have definitely grown since fall. Maybe the food I gave them was not time release but I would imagine it would take some time for it to release. What I used was Jobe's rose spikes. I decided, after some input, that these might not be the best choice for roses. So I broke them up with a hammer and used the pieces in my pansy pots. Perhaps this food is not dependent on a certain degree of warm soil.

I planted some of these pansies probably November and some in December. I think your idea for planting in October makes good sense. I am pleased with the type of food I gave them....next year would use the same thing or something similar so I don't have to keep reapplying.