The old rats who ate blueberries, which contain more anti-oxidants than any other fruit or vegetable tested to date, not only improved their previous scores, but also outperformed any other group of old rats. Now, from a gardening standpoint, this is not very exciting news. Blueberries demand very acidic soil, and our simply does not match up. Furthermore, they're whiney about wind, fussy about fertilizer, and positively perverse about pruning. Spinach is the answer.
Spinach grows in a wide range of soils provided they are moist and fertile.
Spinach devotees should seed about every ten days for a continuous supply. And keep right on seeding into August, as spinach will tolerate a light September frost. After plants emerge, thin them so they are approximately three inches apart. Space rows about a foot apart. Keep garden soil moist, but not water-logged.