Companion plants for fruit trees, including apples, pears, peaches, cherries, and plums. Great article with lots of good information. http://statebystategardening.com/state.php/il/newsletter-stories/fruittree_friends/
Cucumbers and lettuce can be grown beneath sunflowers to take advantage of the shelter they offer. Melons also need protection from the sun's harsh rays and grow well beneath sunflowers. Bush bean varieties, such as wax, lima and green beans, are good sunflower companions. Aphids also like to attack sunflowers, but they do little damage because of the sunflowers' thick stalks and overall toughness. For aphid infestation, plant a few sunflowers to act as distracting decoys.