How Deep Do Garlic Roots Need to Be for Growth?

Timing

• Depending on your location and the variety being grown, garlic can be planted in fall or late winter. However, fall-planted crops consistently lead to bigger yields. Like spring-blooming bulbs, garlic requires a period of cold to prepare for spring growth. By planting in fall, this necessary vernalization -- 40 days at or below 40 degrees Fahrenheit -- occurs naturally over winter. If garlic doesn't receive this cold period, it remains a single, onion-like bulb rather than forming individual cloves. A general guideline is to plant about one month before the ground in your area normally freezes.

Depth

• Planting garlic at a depth of 2 inches provides adequate coverage for most fall plantings, but varies with other considerations. The goal in choosing the right depth relates to moderating soil temperatures. In more southern areas of the United States, 1.5 to 2 inches accomplishes this. In northern areas, 3 to 4 inches gives better results. In the far north, 6 inches is not uncommon.

Preparation

• Preparing garlic for planting is still a job best done by hand. Gently twist off the outer skins and separate the head, taking care not to damage the flat rooting plate -- necessary for root growth -- at the bottom of each clove. The larger the clove, the larger the head it will produce. Set aside small or damaged cloves for cooking; plant only the biggest and best. Garlic from a source in a growing zone similar to yours will provide the best results when planted at the proper depth.

Planting

• Some garlic varieties do fine with any side planted down; others struggle and yield less unless planted with the clove's narrow tip pointing up. Take time to place cloves at the proper depth and orientation for the most abundant crop. Plant your cloves in fertile, loamy soil with lots of organic matter and full sun. Mulch immediately after planting to minimize temperature fluctuations and extend time for root growth. Once active top growth begins in spring, water 1 to 2 inches weekly and keep weeds at bay. When tops begin to yellow, usually in late summer, harvesting time has arrived.