Why did my winter pansies die?

I recently planted about 20 winter pansies in window boxes, which had previously contained marigolds. Despite the mild weather, and ensuring that they were not allowed to totally dry out, only 4 have survived. Could it be that the previous flowers somehow affected the new ones?

Why did my winter pansies die?
there is a disease called pansy sickness, you need to change the compost, viruses build up in the soil.
Reply:i pissed on them whilst walking home after a night out ;-)
Reply:its been very wet and this will effect them the soil may be water logged at the bottom and this will cause them to die or it could be bad plants or insect or slug problem as it is warm the flies ect haven't died dont know about the marigolds to be sure change soil if you can or feed the soil
Reply:Probably more likely that you have some desease in the soil ... or lack of nutrients ... throw away the old compost and replace with new .... and feed them regularly too
Reply:It could have been that they were planted too deeply. In SoCal(where I am) Pansies get "crown rot". That's when the plant has totally wilted and you can just pick it up, with the root ball detached. Pansies must be planted a little high, that is with their rootball a little bit above the soil(ground or pot). I adore Pansies but I won't even plant them in the ground anymore. If you want to try again, just make sure you plant them high :-)
Reply:They didn't die; they're just wintering in San Francisco and South Beach.
Reply:Are you sure the pansies didnt get AIDS?????
Reply:did you use good soil? plant food? watered daily? good amount of sun? (not TOO much)
Reply:They might not be dead, just dormant. They often reseed themselves but of course will not be showing their faces until it gets a bit sunnier and the weather is not quite as wet. They are cool season annuals, but if your soil is good, they will survive. Did you feed them or water them appropiately? Lots of annuals can be planted together; this should not affect the outcome unles you marigolds were diseased in some way.
Reply:If it is a annular flower it will die off.Have to replace next season.Winter one have to be protected from the cold.Merigold would'nt affect them.Did you know if you leave the marigold buds in the dirt they will reproduce fron the sniped off flower when they die.Just pick off and throw anywhere and they grow,i know cause i hace hundreds.Wait and see if pansy is dead.