Planting by the phase of the moon is a technique used to speed germination and influence growth and production of fruit based on the lunar cycle. The type of plant being grown determines the phase in which it should be planted, as each phase of the moon affects plant growth in a different way.
Planting by the phases of the moon finds its roots in ancient Sumeria, some 3,000 years before the birth of Christ. Ancient Romans relied on the phases of the moon to determine both planting and harvesting times. Although many farmers and gardeners view planting by the phases of the moon as mere folklore or superstition, interest has recently revived as a "new age" concept with numerous groups and garden forums springing up to share knowledge and communicate with others with similar interests.
The gravitational force of the moon causes an increase in moisture in the soil at specific points in the lunar cycle and decreases in other phases. Supporters of gardening by moon conclude that increased moisture causes seeds to swell, speeding germination and influencing growth. A decrease in moisture may indicate the time for harvest, depending on the desired use of the plant.
According to the University of Illinois Extension, there is no scientific evidence that planting by the phases of the moon affects plant growth; yet, the Farmer's Almanac, a trusted resource for gardeners since 1818, bases its planting dates on the phases of the moon.
During the new moon, the gravitational pull of the moon draws moisture to the upper levels of the soil and causes seeds to swell. Moonlight also increases at this time and is thought to produce balanced leaf and root growth. It is the favored time for planting lettuce, spinach and grains.
The second quarter is thought to produce leaf growth as the gravitational pull decreases and moonlight is strong. It is the ideal time for planting crops that grow above the ground and contain seeds in the fruit. Melon, peas, beans, squash, peppers and tomatoes are thought to thrive if planted during the second quarter.
The moon begins to wane (get smaller) after the full moon, but the gravitational pull remains high. Decreasing moonlight combined with high moisture provides the ideal circumstances for root crops. Beets, carrots, onions and potatoes are thought to thrive when planted after the full moon.
The Fourth Quarter
The fourth quarter suffers from both a decrease in gravitational pull and moonlight and is considered a rest period for plants. Harvesting, transplanting and pruning should be done during the fourth quarter.