Garlic (Allium sativum) provides a welcome companion to lettuce (Lactuca sativa). Aphids and other soft-bodied insects are drawn to the succulent lettuce leaves, and they can decimate your crop. Garlic naturally repels these pests so your lettuce can reach maturity. Both garlic and lettuce share similar care and culture requirements, so you can plant smaller leaf lettuce varieties with garlic in a container.
Lettuce has shallow roots, but garlic requires enough room for bulbs to form. Containers with a 10-inch depth and a diameter or width of at least 20 inches provide optimum room for multiple garlic and leaf lettuce plants. Use a container with bottom holes to allow excess water to drain. A standard peat-free potting soil or a soil formulated for vegetable plants provides a suitable growing medium, or make your own soil by combining equal parts potting soil and compost. The compost provides nutrients to the plant while the potting soil improves drainage.
Garlic is typically planted in mid to late fall for late spring or early summer harvest, while leaf lettuce can grow year-round in a mild climate. Break apart the garlic bulb into cloves and sow them with the flat ends down and the pointed tip 3 inches deep. Space the garlic 6 to 8 inches apart in all directions. Sow two or three small leaf lettuce seeds directly on the soil surface between the garlic cloves. Cover the seeds with a thin layer of soil and water the container until the excess just begins to drip from the bottom.
Both garlic and lettuce grow best in full, all-day sunlight. Set the container near a south-facing wall in winter to optimize light exposure and warmth during cooler weather. Checking soil moisture daily ensures the container is watered before more than the top 1 inch of soil begins to dry, resulting in healthier growth. The plants may not require fertilizer in compost-rich soil or potting soil that already contains a fertilizer at planting. If the lettuce leaves are pale or growing poorly, mix 1/2 teaspoon of a soluble vegetable fertilizer, such as a 24-8-16 blend, with 1 gallon of water and water the plants with the solution.
Reap What You Sow
Leaf lettuce varieties are often ready to harvest in a month. Cut individual leaves from the plant as needed after they reach their full size, or cut back the entire plant to 1 inch above the soil surface. New leaves grow in, providing a second harvest. Garlic leaves yellow and begin to fall over when they are ready to harvest. Garlic bulbs store best when the soil in the pot is allowed to dry out almost completely in the last two weeks of bulb formation before harvest, just as the leaves begin to yellow. Harvest the last of the lettuce at this time so it doesn't wilt and die when you reduce water for the garlic.
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