How to Hill Up Potato Plants: Boost Yields With This Simple Technique

Hilling potato plants doubles your harvest with just a shovel and 10 minutes of work. 🌱 I learned this trick after watching my first crop produce only a handful of small tubers—until I tried hilling.

The technique isn’t complicated, but it transforms how potatoes grow underground, encouraging more tubers to form along the stems.

This method works for any potato variety, whether you're growing in raised beds, containers, or traditional rows. You’ll need a shovel, some loose soil or compost, and a sunny spot where potatoes can spread their vines.

The goal is to gradually mound soil around the stems as they grow, creating more opportunities for tubers to develop.

By the time harvest season rolls around, you’ll pull up potatoes that are larger, more numerous, and less prone to disease. The process also keeps plants stable in windy conditions and prevents greening (the toxic compound that forms when potatoes see too much light).

Even if you’ve struggled with potato yields before, this technique delivers reliable results.

Timing is everything—start hilling when plants reach 6 inches tall, then repeat every 2-3 weeks until flowering. Avoid piling soil too high or too early, as this can stress the plants. With just a little extra effort, you’ll transform a modest potato patch into a high-yielding harvest.

What you need

Step-by-Step instructions for hill up potato plants

Here's the foolproof method I use every season to get bigger, healthier tubers.

Don't rush this step. Hill potatoes too early and you'll smother the plant. Wait until your potato plants have 4-6 sturdy leaves and reach about 6 inches tall—this usually happens 3-4 weeks after planting. You'll know they're ready when the stems feel firm and the leaves develop a deep green color.

I always check by gently pressing a leaf—if it springs back immediately, the plant's strong enough. Avoid hilling in cool, wet weather. The soil should be warm to the touch and slightly dry at the surface to prevent rot.

Use a shovel or your hands to mound 3-4 inches of loose soil against the plant stems, leaving the top leaves exposed. Don't bury the entire plant—just cover the lower half of the stem. This encourages more tubers to form along the buried portion while keeping the growing tip exposed to light.

I like to work in the morning when soil is still cool, which helps prevent stress. If your soil is heavy clay, mix in some compost first to improve drainage. The goal is to create a gentle slope rather than a sharp mound—this prevents soil from sliding away during watering.

Hill again when new growth reaches 6 inches above the previous mound, continuing until late June or early July (about 2-3 times total). Each time, add 2-3 inches more soil, building up the mound until it reaches the plant's base. You'll see new leaves emerge from the soil surface—these are your signal to keep going.

Stop hilling when the plants start flowering heavily. Overdoing it at this stage can stress the plant and reduce tuber formation. By then, your mound should be about 8-12 inches tall, depending on your variety and growing conditions.

After hilling, water deeply to settle the soil around the stems. Keep the area consistently moist but not soggy—potatoes need about 1-2 inches of water per week, delivered at the base rather than overhead. I use a soaker hose to avoid disturbing the mounds.

Watch for blossoms turning brown—this is your harvest cue. Stop watering 1-2 weeks before digging to let skins toughen. The plants will yellow and die back naturally, signaling tubers are ready. I always mark the location with stakes so I don't accidentally dig in the wrong spot.

Let freshly dug potatoes cure in the sun for 1-2 hours before storing. This toughens the skins and prevents bruising. Choose a cool, dark place (around 45-50°F) with good airflow—basements or root cellars work best. Store in single layers with paper between rows to prevent rot.

Check stored potatoes monthly and remove any that sprout or soften. Properly hilled potatoes often yield 30-50% more tubers than unhilled plants. The key is patience—rushing any step reduces both quantity and quality. Next season, try this with your second-early varieties for even better results!

Tips & tricks for perfect potato plant hilling

These simple strategies will help you maximize your potato harvest without the guesswork.

Timing Secret: In Step 1, when checking plant readiness, look for the "bend test"—gently press a leaf near the stem. If it springs back immediately, the plant's strong enough. If it stays bent, wait another 2-3 days. I learned this the hard way after smothering plants that weren't ready, which stunted growth for weeks.

Soil Strategy: For Step 2, if your garden soil is heavy or compacted, mix in 1-2 inches of compost or aged manure into the mound you're creating. This improves drainage and gives those developing tubers extra nutrients. The goal is loose, aerated soil—not packed dirt—that lets roots breathe and expand freely.

Visual Cues: In Step 3, watch for these signs you've hilled enough: new leaves emerging from the soil surface (good!) and stems starting to thicken near the base. When you see heavy flowering, that's your cue to stop—over-hilling at this stage actually reduces yields by stressing the plant. Think of it like giving your potatoes a supportive pillow rather than a straitjacket.

Harvest Hack: For Step 5, when curing your potatoes, place them in a single layer on a baking sheet in direct sunlight for that 1-2 hour cure. This toughens the skins and prevents bruising. I always do this on a warm afternoon when the sun is strongest—it's like giving your potatoes a natural "tanning session" before storage.

Frequently asked questions

Got questions about hilling up potato plants? You’re not alone—this technique can feel a little tricky at first! Below, we’ve rounded up the most common queries to help you grow like a pro.

When is the best time to hill potato plants?

Hill potatoes after they’ve sprouted 6–8 inches tall and before flowers appear (usually 3–4 weeks after planting). For early varieties, do it when stems are pencil-thick. Late varieties can handle a second hilling later in the season. Pro tip: Avoid hilling too early—you want sturdy stems to support the weight!

How often should I hill potato plants?

Most gardeners hill potatoes 2–3 times during the growing season, spacing hills about 2–3 weeks apart. Stop hilling when the plants start flowering or when the tops turn yellow (a sign of maturity). Overdoing it can stress the plant or invite disease. Watch for: Loose soil piling up around stems—this is your cue to hill again!

What if I forget to hill my potatoes?

Don’t panic! While hilling boosts yields, potatoes can still grow without it. However, you’ll likely get fewer tubers, and they may be smaller or exposed to light (turning green and toxic). If you missed the window, focus on keeping weeds away and watering deeply. Silver lining: You can still harvest smaller potatoes—just dig gently around the base of the plant.