If you’re a gardener in the Land of 10,000 Lakes, knowing when to plant potatoes in Minnesota is the key to a great harvest. Getting the timing right means your spuds grow strong before the summer heat and have plenty of time to mature.
Planting too early risks frost damage to your seed potatoes, while planting to late can mean smaller tubers. This guide will walk you through the optimal spring schedule and simple steps for success.
When to Plant Potatoes in Minnesota
The classic rule for Minnesota is to plant your potatoes around the time of the last spring frost. For most of the state, this target window is from late April through mid-May.
Here’s a more detailed regional breakdown:
- Southern Minnesota (Zones 4b-5a): Aim for late April to early May. Cities like Rochester and the Twin Cities metro area often fall into this range.
- Central Minnesota (Zones 4a-4b): Target early to mid-May. This includes areas around St. Cloud and Mankato.
- Northern Minnesota (Zones 3a-3b): Wait until mid to late May. Gardeners in Duluth, Bemidji, and the Iron Range should be especially patient for the soil to warm.
A perfect soil temperature cue is 45°F to 50°F. You can use a simple soil thermometer to check this a few inches deep. Another old farmer’s trick is to watch for nature’s signs, like dandelions starting to bloom.
Why Soil Temperature Matters More Than the Calendar
While calendar dates are a helpful guide, your local soil condition is the real boss. Planting in cold, soggy soil is a common mistake.
Cold soil delays sprouting and can cause seed pieces to rot instead of grow. If the soil sticks together in a wet ball when you squeeze it, it’s to wet to work. Wait until it crumbles slightly.
Well-drained soil that has begun to warm ensures your seed potatoes get off to a vigourous start, setting the stage for healthy plants.
Choosing the Right Potato Varieties for Minnesota
Selecting varieties suited to our shorter growing season improves your results. Look for early to mid-season types that mature in 70-100 days.
Some excellent, reliable choices include:
- Dark Red Norland: Early, smooth red skin, great for boiling.
- Yukon Gold: Mid-season, buttery yellow flesh, versatile.
- Kennebec: Mid-season, high yield, excellent for storing.
- Adirondack Blue: Unique purple flesh, holds color when cooked.
- Russet Burbank: Classic baking potato, requires a longer season but does well in central/southern MN.
Always buy certified disease-free seed potatoes from a garden center or reputable catalog. Using potatoes from the grocery store is risky, as they may carry disease or be treated to prevent sprouting.
Step-by-Step Planting Guide
Follow these steps for a perfect planting day.
1. Pre-Sprout Your Seed Potatoes (Optional but Recommended)
About 2-3 weeks before your planned planting date, place your seed potatoes in a cool, bright spot. This process, called “chitting,” encourages short, sturdy green sprouts.
It gives your plants a head start, which is especially valuable in our northern climate.
2. Prepare Your Seed Pieces
A day or two before planting, cut larger seed potatoes into pieces. Each piece should be about the size of a golf ball and have at least 1-2 healthy “eyes” or sprouts.
Let the cut pieces air-dry for a day to form a protective callus over the cuts. This helps prevent rot once their in the ground.
3. Prepare the Garden Bed
Potatoes thrive in loose, well-drained soil with a slightly acidic pH (5.8-6.5). Choose a spot that gets full sun.
Work in several inches of compost or well-rotted manure to improve soil structure and fertility. Avoid fresh manure, as it can promote scab disease on the tubers.
4. Planting Depth and Spacing
Plant your seed pieces with the eyes facing up. A good rule is to plant them 3-4 inches deep.
Space the pieces about 12 inches apart in the row, with rows spaced 2.5 to 3 feet apart. This gives the plants room to grow and makes hilling easier later on.
Caring for Your Potato Plants
Consistent care through the season protects your crop and boosts yield.
Watering and Hilling
Keep the soil consistently moist, but not waterlogged. About 1-2 inches of water per week is a good target, increasing during hot, dry spells.
When plants are about 6 inches tall, begin “hilling.” Mound soil up around the base of the plant, covering the stems halfway. Repeat this every few weeks as plants grow.
Hilling is crucial! It protects developing tubers from sunlight (which turns them green and toxic), supports the plant, and encourages more potatoes to form along the buried stem.
Fertilizing and Pest Watch
A balanced, low-nitrogen fertilizer applied at planting and again at hilling is beneficial. To much nitrogen leads to lots of leaves but few potatoes.
Keep an eye out for Colorado potato beetles. Hand-pick the orange larvae and adult beetles off plants daily if you see them. Floating row covers can also provide a physical barrier early in the season.
Rotating your potato patch to a different area of the garden each year helps prevent buildup of soil-borne diseases.
Harvesting Your Minnesota Potatoes
You can harvest “new” potatoes carefully by hand once plants flower. For main crop potatoes intended for storage, wait until the plant tops turn yellow and begin to die back.
Use a garden fork to gently loosen the soil and lift the tubers. Let them cure on the soil surface for a few hours, then brush off dirt and store in a cool, dark, humid place.
Properly cured and stored, your homegrown potatoes can last for many months, providing delicious meals long after the garden is asleep under snow.
FAQ: Minnesota Potato Planting
Can I plant potatoes in early April in Minnesota?
It’s usually to risky. Unless you’re in a very protected microclimate in southern MN, soil is typically to cold and wet. Patience pays off for better yields.
What if a late frost comes after I’ve planted?
Potato foliage is sensitive to frost. If a light frost is forecast after sprouts emerge, cover them with row fabric, old sheets, or a light layer of straw. They will often recover from minor damage.
Can I grow potatoes in a container?
Absolutely! Use a large container (like a 15-gallon pot or grow bag) with drainage holes. Follow the same timing and hilling principles, just in a smaller space. This is a great option for limited areas.
How do I adjust planting for a late, wet spring?
If spring is exceptionally cold and wet, delay planting until soil conditions improve. Consider using raised beds, which warm up and drain faster than in-ground gardens. Choosing early varieties can help you catch up.
By following this Minnesota-specific guide, you’ll give your potato crop the best possible start. The reward of digging up your own homegrown spuds is well worth the wait and careful planning.