California grows most of the domestic kiwis available in the U.S. While they ripen in late fall, cold storage keeps them available into mid-spring.
The standard variety Eureka lemons are available year-round, but peak production is between late winter and early summer. Meyer lemons are in season now, peaking between November and March.
Like many leafy greens, lettuce is a cool season crop that can be grown year-round in California. Arizona also produces a large percentage of U.S. leaf lettuce.
As mushrooms can be cultivated indoors, year-round, they are available fresh any time of year. Pennsylvania, California, and Florida are the main producers of mushrooms in the U.S.
Commercial onions are grown domestically in over 20 states, and they are available year-round as storage vegetables.