as all these vegitables are imported, they are preserved in nitrogen cooling system, which help in reducing oxygen around the vegitables during the storage. when the vegitables are out of containers and in the market, they should kepp in in cool environment to maintain freshness.
the idea is, the longer these crops stays in the fridge (nitrogen),, the sooner they spoil when they are kept out.
you want to have fresh, goodloking vegitables, buy it early as they come from the storage, have an icebox in your car with some ice just to keep it cool, and store in sealed containers/bags in your fridge.