Year-round availability made seasonality an aesthetic choice rather than a constraint. Several separate pressures have been quietly turning it back into a practical one.
Global supply flattened the calendar
Growing the same crop in opposite hemispheres, combined with cold storage and air freight, made most produce available in every month somewhere in the world.
Shoppers adapted quickly, and a generation grew up with no particular expectation that an ingredient would be absent for part of the year.
The cost of that flattening was carried by transport and storage, which stayed cheap enough for long enough that few buyers thought about it.
Transport and storage costs are now visible
When freight and refrigeration get more expensive, out-of-season produce is the first category to show it, because those costs form a large share of its price.
A kitchen watching its food cost notices that the same vegetable swings sharply in price across the year, and starts writing menus that follow the cheaper months.
Shoppers make the same adjustment less deliberately, buying whatever is priced attractively that week, which usually means whatever is in local surplus.
Storage changes flavour in ways cooking cannot fix
Produce picked early to survive a long journey continues to soften but does not continue to develop sugars and aromatic compounds in the same way.
This is why an out-of-season tomato can be structurally fine and still taste thin, and why cooks compensate with acid, salt and concentration rather than with heat.
In-season produce arrives with that development already done, so it needs less intervention and fewer supporting ingredients to taste like itself.
Shorter supply chains reward growers differently
A grower selling into a long chain must choose varieties that travel and store, which historically meant sacrificing flavour for durability.
Selling locally removes that constraint and allows varieties bred for eating rather than for shipping, which is why regional markets often carry produce no supermarket lists.
As more kitchens buy that way, the varieties themselves come back, and seasonality returns as a consequence of the sourcing rather than as a stated policy.
Menus are absorbing the change structurally
Restaurants that once printed a fixed card now print a short one, or leave sections deliberately vague, so that substitutions do not require a reprint.
Home cooking is shifting the same way, towards methods that accept whatever vegetable is good rather than recipes that name one and fail without it.
Seasonality returning as flexibility, rather than as restriction, is what makes it durable this time.