In recent years [and for generations among indigenous populations], companion planting has emerged as a common technique aimed at exploiting the benefits of the relationships between specific plants to naturally improve crop flavor, health, and vigor.
More simply, companion planting is a type of polyculture where two plant species are grown together because it is known or theorized that they synergistically improve each other’s growth. However, empirical evidence of the actual efficacy of such practices is sometimes lacking. This helpful guide helps to discern between fact, folklore, and traditional practice.
Garden Wisdom & Know-How: Everything You Need to Know to Plant, Grow, and Harvest. Black Dog & Leventhal Publishers, 2018.