How To Hill Potatoes

Potatoes are a staple crop in many gardens, prized for their versatility and relatively easy cultivation. One of the most important steps in growing healthy, productive potato plants is hilling. Hilling involves mounding soil around the base of the plants as they grow, which encourages tuber development, prevents greening, and improves drainage. In this guide, we’ll walk you through the why, when, and how of hilling potatoes to ensure a bountiful harvest.

Why Hill Potatoes?

Hilling serves several key purposes in potato cultivation:

1. Promotes Tuber Growth – Potatoes form along the buried stems of the plant. By hilling, you create more underground space for tubers to develop, increasing your yield.
2. Prevents Greening – Exposure to sunlight turns potato skins green, producing solanine, a toxic compound. Hilling keeps tubers covered and safe from light.
3. Improves Drainage – Mounded soil helps prevent waterlogging, reducing the risk of rot and fungal diseases.
4. Supports the Plant – As potato plants grow taller, hilling provides stability, preventing them from toppling over in wind or heavy rain.
5. Weed Suppression – Burying weeds under fresh soil minimizes competition for nutrients.

When to Hill Potatoes

Timing is crucial when hilling potatoes. The process should begin when the plants are about 6–8 inches tall and repeated every few weeks until the plants flower or stop growing vigorously. Here’s a general schedule:

• First Hilling: When plants reach 6–8 inches tall.
• Second Hilling: 2–3 weeks later, when plants have grown another 6 inches.
• Final Hilling: Just before the plants flower (usually around 4–6 weeks after planting).

Stop hilling once the plants begin flowering, as disturbing the roots at this stage can reduce yields.

How to Hill Potatoes: Step-by-Step

1. Prepare the Soil

Before planting, ensure your soil is loose, well-draining, and rich in organic matter. Potatoes thrive in slightly acidic soil (pH 5.8–6.5). If your soil is heavy clay, amend it with compost or sand to improve texture.

2. Plant Seed Potatoes Correctly

• Cut seed potatoes into chunks, each with at least 1–2 eyes.
• Plant them 4–6 inches deep and 12–15 inches apart in rows spaced 2–3 feet apart.
• Cover with soil and water thoroughly.

3. First Hilling (6–8 Inches Tall)

Once the plants are about 6–8 inches tall:

• Use a hoe, rake, or your hands to gently mound soil around the base of each plant, covering about half of the stem.
• Leave the top few inches of foliage exposed.
• Avoid compacting the soil too tightly, as potatoes need loose earth to expand.

4. Second Hilling (2–3 Weeks Later)

Repeat the process when the plants grow another 6 inches:

• Add another 3–4 inches of soil, straw, or compost around the stems.
• Ensure no tubers are exposed to sunlight.

5. Final Hilling (Before Flowering)

One last hilling ensures maximum tuber protection:

• Mound soil up to 6–8 inches high around the plants.
• If using straw or mulch, add a thick layer to keep the soil cool and moist.

Alternative Hilling Methods

• Straw Hilling: Instead of soil, use straw or mulch to cover the stems. This keeps tubers clean and makes harvesting easier.
• Container Hilling: If growing in pots or grow bags, simply add more soil as the plants grow, filling the container gradually.

Common Mistakes to Avoid

• Hilling Too Late – If you wait until plants are too tall, you risk damaging roots and exposed tubers.
• Using Compacted Soil – Dense soil restricts tuber growth; always keep it loose.
• Over-Hilling – Burying too much foliage can stress the plant. Leave at least a third of the plant exposed.
• Neglecting Watering – Hilled soil dries out faster, so maintain consistent moisture (1–2 inches per week).

Harvesting Your Potatoes

Once the plants flower and the foliage begins to yellow and die back, stop watering to allow the skins to toughen. After 1–2 weeks:

• New Potatoes: Dig gently around the plant for tender young tubers.
• Mature Potatoes: Wait until foliage has fully died, then harvest all tubers carefully to avoid bruising.

Conclusion

Hilling potatoes is a simple yet essential practice for a successful harvest. By following these steps—starting when plants are young, repeating every few weeks, and using loose, well-draining soil—you’ll encourage healthy tuber development and protect your crop from sunlight and pests. Whether you’re growing in garden beds, containers, or straw bales, proper hilling ensures a plentiful yield of delicious, homegrown potatoes. Happy gardening!