Planting sprouted potatoes is an easy way to grow potatoes, from potatoes! Once potatoes get sprouty, they’re not great for eating but they’re perfect for planting and it’s surprisingly easy to grow your own fresh new potatoes at home in just a few weeks.
It’s happened to everyone, you forget a few potatoes in the pantry and they start to get green and sprouty. Once potatoes start to sprout, they actually start to produce toxins in their skin that are not great for your digestive system, so eating sprouted potatoes is not the best option.
Throwing them out or composting them seems a shame when with just a tiny bit of effort (and a small amount of soil), you can grow fresh new potatoes from old sprouty potatoes. You don’t need a green thumb, and potatoes actually thrive on relatively poor soil and benign neglect.
It’s actually only a tiny bit more complicated than sticking the potatoes in soil and waiting.
You can plant them, wait a few weeks and harvest tender “new potatoes,” or wait the full season and harvest a whole crop of full-grown regular storage potatoes.
New potatoes are quick, but generally, only yield about 2 to 5 pounds of small tender potatoes per pound planted. Full-season potatoes will usually yield around 15 to 20 pounds of potatoes per pound planted.
Unlike planting sprouted onions or planting sprouted garlic, the process for planting sprouted potatoes isn’t all that different from growing potatoes in general. We tend to grow potatoes in raised beds, but they also do fine straight in the soil. Many people choose to plant sprouted potatoes in containers, and they do well in large pots and in grow bags.
That said, if you’re looking up how to plant sprouted potatoes, there’s a good chance you haven’t grown potatoes before and you have a lot of questions about the process.
Plant sprouted potatoes in full sun to part shade, in average garden soil, about 6 to 8” deep and 12 to 16” apart. I don’t bother cutting them, just plant them whole. They can be planted as early as 4 weeks before the last frost in spring, or as late as 8 weeks before the first winter frost. Sprouts should be facing up.
For small tender new potatoes, allow them to grow at least 8 weeks, until the plants set flowers.
For full-sized storage potatoes, allow them to grow all season long until the plants die back. That’s usually 60 to 100 days after planting, depending on the variety. Harvest the potatoes after the plants have been dead for about 2 weeks (they develop their skins for storage after the plants die back).
That’s just the quick answer, and if you want more details, I’ll walk you through the process, one question at a time.
It’s spring planting season and you’re getting your seed potatoes ready But when you open the bin where you stored them over winter, you discover some have grown sprouts several inches or even feet long! What should you do? Can you still plant potatoes with long sprouts or should you toss them in the compost pile?
Sprouting is a potato’s natural way of preparing to grow a new plant. Given the right conditions of warmth and humidity, dormant potatoes will begin sending out shoots from their eyes to start the growth process. However long sprouts don’t necessarily mean the potatoes are no longer viable for planting. With some care, you can still make use of sprouted potatoes.
Why Potatoes Sprout
Potatoes sprout when stored in temperatures above 40-50°F. The higher the storage temperature, the faster they will sprout. This is because warmth breaks the potato’s dormancy and signals it to begin growing. Sprouting causes the potato to start converting its starch reserves into energy to support new shoot and root growth.
Should You Remove Long Sprouts?
Resist the urge to snap off those long sprouts! The sprouts are tapping into the potato’s internal resources in order to grow. Removing sprouts forces the potato to expend more energy to produce new ones. As long as the sprouts are healthy, leave them intact when planting.
However, thin weak sprouts that seem likely to break off in handling can be pruned. Also, potatoes with sprouts longer than 3 feet may not have enough remaining nutrients to grow well. In that case, removing excessively long sprouts can conserve energy.
Planting Potatoes with Long Sprouts
With care, potatoes with lengthy sprouts can still be planted with good success:
- Handle gently to avoid damaging long sprouts
- Allow sprouts to grow upright or lay sprouts in planting hole
- Bury potato 4-6 inches deep with sprouts pointing upward
- Water well and provide consistent moisture
It’s fine to plant potatoes with sprouts even 1-2 feet long. Just take care in handling and planting not to break them. Bury the potato deep enough to cover the sprouts fully. Potato plants form tubers best when sprouts reach light, so point them toward the surface.
Should You Hill Potatoes?
“Hilling” refers to mounding up soil around the base of potato plants as they grow. Hilling encourages more root growth and prevents tubers from greening above ground.
With deep planting of long-sprouted spuds, hilling isn’t strictly necessary. However, it can still boost yields, especially in hot climates where tubers grow close to the surface. Hill up added soil or mulch when plants are 4-8 inches tall.
Storing Potatoes to Prevent Sprouting
To discourage sprouting in storage:
- Cure freshly harvested potatoes 1-2 weeks before storage
- Store in complete darkness around 40°F with good air circulation
- Avoid high humidity which promotes sprouting
Avoiding light, keeping cool, and providing air flow are key to preventing sprouts. Check regularly and remove any sprouting potatoes from storage to prevent spreading. With proper storage, most potatoes will stay dormant 4-6 months.
Planting Store Bought Potatoes
Grocery store potatoes often won’t grow well due to sprout inhibitors and potential diseases. Purchase certified disease-free seed potatoes from garden stores for best results.
However, store bought potatoes can be planted by first washing off inhibitors, then “greening” them by exposing to light and warmth to induce sprouting. Wait until sprouts are 1-2 inches long before planting.
Don’t discard those long-sprouted spuds just yet! With some careful handling, potatoes with lengthy sprouts can still be planted successfully. The key is avoiding damage to sprouts and planting deep enough to bury them fully. With good growing conditions, the potato’s remaining nutrients can still fuel ample tuber production. Trust nature’s wisdom and give those sprouting potatoes a chance to grow.
How Far Apart Do You Plant Sprouted Potatoes?
They’re planted about 12 to 16 inches apart, in rows 2 to 3 feet apart. If you’re planting a “patch” rather than rows, you can just plant them 16” apart in all directions.
When Can You Plant Sprouted Potatoes?
Generally, potatoes are planted in the spring, about 4 weeks BEFORE the last frost date in your area. That’s 4 weeks before you’d put out your tender garden crops like tomatoes and peppers. They take a while to sprout up out of the soil, and during that time they’re insulated in the earth.
Four weeks before the last frost is about 2 weeks before the first spring dandelions.
That’s the earliest you can plant potatoes outdoors, and that’s ideal if you grow the potatoes all summer and get the maximum yield of full-grown potatoes.
You can, however, plant potatoes anytime during the summer and even into early Autumn, provided you have at least 8 weeks until things turn cool and you get your first hard winter frosts.
Eight weeks will only yield very small new potatoes, and you’ll get just a bit more than the weight you originally planted. Not bad, given that new potatoes are a real treat, and those old sprouty potatoes were going to the compost heap anyway.
If you do plant them in the early spring, as I did, they’ll pop up about 2 weeks later, right alongside your dandelions (still a few weeks before the last frost). They can handle those last few touches of frost in spring, provided they’re mild.
Real life. How we plant and save our potato seed (and it works)!
FAQ
Can I plant potatoes with very long sprouts?
It doesn’t matter how long the sprouts are, just try to have two sprouts on each section you’re planting. If the whole potato only has one or two sprouts, then leave it and plant it whole. Cut them a couple days in advance.
How sprouted is too sprouted for potatoes?
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Firm Texture:Ensure the potato remains firm to the touch and not mushy or soft.
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No Green Areas:Avoid potatoes with green discoloration, as this indicates the presence of solanine, a toxic compound.
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Small, Easily Removed Sprouts:If sprouts are small and can be easily removed, the potato is likely still safe to eat.
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No Wrinkles or Shriveled Skin:If the potato skin is wrinkled or shriveled, it’s a sign of spoilage, and it’s best to discard it.
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Cut off the sprouts and any green areas:Before cooking, cut off the sprouts and any green parts with a generous margin.
What happens if you plant a whole potato?
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Growth and Production:When you plant a whole potato, the “eyes” (buds) on its surface will sprout, and these sprouts will develop into multiple potato plants. Each plant will then produce its own set of new potatoes.
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Original Potato’s Fate:The original potato you planted will not remain a whole potato. It will start to shrivel and rot as it provides nutrients for the new growth emerging from its eyes.
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Potato Size:While you might get more potatoes in total from planting a whole potato, the individual potatoes might be smaller due to the increased competition for resources among the multiple plants developing from a single potato.