It's always the right time to start your stockpile. Basic staples and long-lasting goods can be bought in surplus and tucked away in small doses, rather than trying to create a fully stocked emergency cupboard all at once. It's a good idea to have an emergency supply at hand for immediate issues your household may run into, such as storms or power outages.
Keeping non perishable goods is a good idea to have around in general for possible short term food shortages that may arise. In cases of preparing for the long term possible shortages, it is never too late to prepare. Canning, freezing, vaccum sealing and dehydrating food products a few at a time doesn't take up too much time.