I know this is an older post, but I've had amazing luck with my pansies so I thought I'd reply anyway, for what it's worth. I have several pansies that I planted in the early spring in pots and then put in planters outside my front door. We get LOTS of sun there during all seasons, and I was advised to water them every morning to help keep their roots cool. I did, and I dead-headed them from spring until now. I'm in zone 5b and it's getting pretty cold now, but they just keep flowering! They're beautiful and healthy, and have new buds even though they were beaten by rain yesterday and today. I feel strange because all my neighbors have gotten rid of their spring/summer flowers and have put out the hardy chrysanthemums. I'm the only one with pansies still out there! But I still love them and me being me, I tell them so daily.
The same person who advised me about keeping their roots cool said she put them under her deck during the winter (it snows here and sometimes gets as cold as -20 with windchill) and they lived and flowered the following spring. That's why I planted them in pots--so that I could easily remove them from the planters and place them under my deck for the winter. I'll let you all know what happens with them in the spring of 2017!
I should mention that I sometimes use Miracle Gro Bloom Booster Flower Food with them. Oh, and my marigolds are still in full bloom mode too! HTH.
