Human survivors should anticipate the shock of season change in accordance with their pre position and anticipated post position. Crops already in the ground may produce in the Aftertime climate if close enough to what they expect, and if pollination has already occurred. However, this should not be counted on, as the number of variables is higher than man allows for. Most crops will sicken and fail to produce, regardless of man's expectations. The guidelines for Aftertime planning should be:
There are variables mankind does not normally consider that will be affecting life after the shift, such that an assumed plant
or animal life would falter and simply die off, and others flourish. These variables have been present in the past, in your
ancestors, when they migrated to new lands, but are not usually passed down to offspring. An immigrant to a new land
would bring seed, perhaps even a pair of prized livestock, and find even with the latitude and seasons similar to the home
land, all die. Local fauna and flora, bacteria, rodents, affects the immigrants, though often unseen by the humans with high
hopes. Thus, the failure is a disappointment but the reasons for failure not grasped. In like manner, because of factors like
acidity of rain, weather shock in insects or even bacteria in the soil, even plants and animals familiar to an area may
succumb, and die off. Opportunistic germs today are affecting the biology of the world, such that pre-existing illness is
causing animal life to sicken. Germs are migrating, infecting in areas not usual, and the immune systems of the affected
lowered by the weather extremes and roiling emanations from the Earth's core.
Thus, in addition to the predictable climate you will shift into, you should anticipate failure in restarting your gardens and
herds and flocks. The best plan is a broad plan, so that a failure does not devastate.