Marigold plant dried and died

Though marigold flowers are attractive and last for a longer time compared to some other flowers like mogra, soon after october end the plant started withering and dried up quickly. There seemed to be no obvious reason why the plant was drying up so quickly when it was being watered daily and mineral fertilizers were being added.
Any gardening expert aware of the reason for the quick marigold plant withering can contact any information will be greatly appreciated.