How to Successfully Plant Potatoes That Have Sprouted


Have you ever reached into a forgotten bag of potatoes and found them sprouting, with several “eyes” or buds on each one?  Although you can cut these eyes away and safely eat the potatoes, I wondered if you could let them continue to grow instead.

So, can you plant a potato that has sprouted?  Yes, you can plant a potato that has sprouted.  With the proper care, it will grow into a full-fledged potato plant and produce many potatoes.  There are also ways to improve the potato plant’s chance of survival and increase your yield.

Let’s start off with why potatoes sprout in the first place.  Then, we’ll get into how to plant sprouted potatoes and how to care for the plants as they grow.  We’ll also talk about how to harvest and store potatoes from your plant, along with potential problems and how to avoid them.

Why Do Potatoes Sprout?

Potatoes, like all plants, have a goal to reproduce and create a new generation.  Even in seemingly hostile conditions, they will attempt to do this.

Two potatoes with eyes – they are both sprouting nicely.

Potatoes contain special cells in their buds, which become stems or roots.  Potatoes also contain plenty of nutrients and starches in their flesh, so they have the resources available to sprout and start growing into a new plant.  As long as they are warm enough, potatoes will quickly begin to sprout.

A sprouting potato has eyes or buds, which are bulging sprouts.  Each of these has the potential to grow into its own potato plant.

If you want your potatoes to sprout, then store them in a warm, damp, light environment.

On the other hand, if you are annoyed by sprouting potatoes, there are a few things you can do to prevent it from happening.  First, remember that potato varieties that mature faster will have a shorter dormancy period (dormancy period is the amount of time before they begin to sprout).

Also, make sure to “cure” your homegrown potatoes by leaving them out to dry.  Once cured, store the potatoes in a cool, dry, dark place to slow down the sprouting process.  Finally, avoid storing them together with onions – this seems to make them sprout faster!

Even if your potatoes do sprout, you can cut out the eyes and eat the potatoes, including the skins.  Just make sure that you don’t eat any green skin or flesh from the potatoes.

This green color is caused by solanine, which deters animals from eating potatoes.  Solanine is poisonous, and will make you sick if you eat too much of it!

How to Plant Sprouted Potatoes

There are a few things to keep in mind when you go to plant your sprouted potatoes.  Follow these steps, and you should get healthier plants and more potatoes.  Let’s take them in order.

Wait for the Right Conditions

If you plant your potatoes too early, a late frost could kill them.  You can use this tool from the Farmer’s Almanac to find the date of the last frost for your area.

Remember that these dates are estimates or averages, and a frost could occur slightly later.  To be safe, you can certainly wait until a few weeks after this to plant.

If your potatoes are really sprouting quickly, you could put them in some potting soil in a bucket, under a grow light or near a window.  Then, you can transplant them to the garden later.

long potato sprouts
This potato has sprouted and is really taking off. It can’t be contained!

In order to plant outside, the soil should be thawed (not frozen), but still cool (60 to 70 degrees Fahrenheit).  Generally, mid to late summer is the latest you will want to plant potatoes outside.  Otherwise, an early frost could kill the plants, and frozen ground would make the potatoes difficult to harvest.

Prepare Potatoes for Planting

Now that you have an idea of when to plant, it’s time to prepare the potatoes themselves for planting.  You can certainly plant an entire potato in the ground and let it grow, but there is a better way to get more plants and more potatoes.

First, cut the potato into pieces.  Try to leave one eye on each piece of potato.  That way, you can plant the potato pieces apart, to prevent competition for resources in the soil.

cut potato with eyes
Cut the potato into pieces – aim for one eye per piece.

Then, leave the potato pieces out for a few days, to give them a chance to dry out.  This will help to prevent rot after you plant the potatoes.

While you are waiting for the cut potato pieces to dry out, you can take the next step, which is choosing and preparing a garden site.

Choose and Prepare a Garden Site for Potatoes

Potatoes are not too picky, but if you choose a good garden site to grow them, then the plants will thrive and produce more potatoes for you.

First, identify areas of your garden that get 6 to 8 hours of full fun per day, with partial shade during the rest of the day.  Avoid areas with full shade, since this will inhibit the growth of potato plants.

sunlight through forest
Potatoes need plenty of sunlight. Look at those beautiful rays!

Next, make sure that the soil drains well.  Potatoes don’t like soil that is too soggy, so if needed, add manure or compost to make your soil drain faster.

To find out, dig a hole, and pour some water in it.  If the water drains down into the soil in 10 minutes or less, the soil is well-draining. If your soil drains poorly, you can add compost to your soil to supplement organic material (humus) and improve drainage.

For more information, check out my article on how to make soil drain better.

On the other hand, if you have trouble with dry soil, check out my article on how to treat dry soil.

Keep in mind that potatoes and tomatoes should not be planted together, since they are in the same family and share some of the same diseases, such as early blight and late blight. For more information, check out my article on why you should not plant tomatoes and potatoes together.

Then, check your garden soil’s pH & nutrient levels.  You can use a home test kit, or send it away to your local agricultural extension for testing. To learn more, check out my article on how to test your soil.

Potatoes like acidic soil, with a pH between 4.8 and 5.5.  If your soil pH is too high, one way to lower it is to add elemental sulfur. For more information, check out my article on how to lower soil pH.

If nutrient levels look low, add soil amendments as needed.  A standard 10-10-10 fertilizer should help with the three most important nutrients (nitrogen, potassium, and phosphorus, or N-P-K). For more information, check out my article on the NPK ratio on bags of fertilizer.

Finally, prepare spaces to plant your potatoes.  Dig holes 3 inches deep and 1 foot apart in a row, or else dig a trench along the row.  A trench might work better for potatoes that have formed long sprouts.  Since potatoes start off completely underground, you can use some type of marker (a stick, etc.) to tell you where you planted the potatoes.

When the potato pieces are dry, plant them in your holes or trench, and cover them with soil.  You’re on the way to growing your own potatoes!

Of course, if you want to do something completely different, you can plant your potatoes in straw bales! For more information, check out my article on planting potatoes in straw bales.

Watering Potato Plants

When the top inch or so of soil above the potatoes is dry, give them water.  There is no rule for when this needs to be done; it will depend on temperature, humidity, your soil, and how much water the potatoes use.  Your best bet is to check the soil with your fingers each day to see if it is dry.

You can use your hands to feel new potatoes forming underground near where you planted the sprouted potato.  When these new potatoes begin to form, water the plant heavily, since it will grow rapidly and use lots of water.

Just be careful about overdoing it, especially if you are new at gardening – see my article on over watering plants.

Adding Soil to Potato Plants

With most plants, you put them in the ground and they grow without you having to add any more soil.  Potatoes can grow this way, but you can do even better than that.

Hilling, or building a mound of soil around potato shoots, is a method that will lead to stronger plants and bigger potatoes.  It will also help to prevent sun damage.

Use the “hilling” method to add soil at the base of potato plants as they grow. This will keep the tubers from turning green and inedible due to sunlight exposure.

Hilling is easy to do if you want to try it.  After every 6 inches of growth above ground, add some more soil to cover most of the plant.  However, don’t cover it completely, since photosynthesis requires that some leaves be exposed to the sunlight.

Harvesting and Storing Potatoes

Let’s talk about when and how to harvest potatoes, along with the best ways to store them.

When to Harvest Potatoes

Generally, potatoes will be ready for harvest 18 to 20 weeks after planting the sprouted potatoes.  If you started them in soil indoors, you will want to track from that date, so be sure to write it down!

Before the 18 to 20 weeks are up, you may see your potato plants start to decay.  The leaves will turn yellow, and the plant will die back.  This is not necessarily a cause for alarm, since it is a natural part of the potato life cycle.

If you plant potatoes in a container, you can just dump out the soil and sift through it to find the tubers after the plants die back.

In fact, this is actually a sign that the potatoes are ready to harvest.  If you wait 2 to 3 weeks after the plant starts to die back, the potatoes should be mature and ready to harvest.

Just make sure to keep an eye on the weather forecast.  Frost kills potato plants, just like any other.  The potatoes may be fine if they are far enough underground, but if the ground freezes, it will be difficult to harvest the potatoes.

How to Harvest Potatoes

You can use your hands, although you might want to use gloves if the soil is cold in the fall.  This method is slower, but there is less chance of damaging the potatoes.

You can also dig with a trowel, pitchfork, or other tool.  This will be faster, but has more chance of damaging some potatoes.  Of course, any that get damaged can be washed and eaten immediately.

How to harvest potatoes depends on what you want.  New potatoes are small and soft, with thin skins, and will be found higher up on the plant (and thus buried in less soil).  They are a nice fall crop to go with some of your other vegetables, but they don’t store as well.

Bigger potatoes are the more mature ones with thicker skins, which store better, and will be found deeper down in the soil.

If you leave potatoes in the ground longer, their skins will get thicker, making them easier to store for long periods.

How to Store Potatoes

If you get plenty of potatoes, you will want to make sure to store them properly, so that you can enjoy the bounty of your harvest for months to come.

potatoes
Potatoes, cleaned and ready to store.

First, brush off the dirt from your potatoes.  Avoid scratching them or cutting into them.  You can use a soft, dry brush to do this.  However, don’t wash the potatoes, since this can encourage mold growth.

After cleaning the potatoes, allow them to cure for a few days.  This just means leaving them out to dry a bit.

Once they are cured, store the potatoes in cool, dry, dark place to keep them from sprouting.  When you are ready to cook them, wash the potatoes and prepare them.  If any eyes have sprouted, you can cut them out.

As mentioned above, if you want to sprout potatoes for planting next year, then put them in a warm, damp, well-lit place.

Potential Potato Problems

Growing potatoes is not necessarily all sun and games.  Sometimes, you will encounter problems.  Here are a couple of common problems to look out for.

Diseases

Potato blight, or late blight, is a water mold, and it was responsible for the Irish potato famine in the 1800’s.  If you plant a potato with blight, the disease can spread to your garden.

Potatoes from grocery store could have blight in them, even if they look healthy.  Furthermore, grocery store potatoes are often treated with a sprout inhibitor.  This keeps the potatoes edible longer, but prevents you from growing more of them.

If you want to grow your own potatoes from sprouts, then look for certified disease-free seed potatoes from a garden supply center.

Pests

There are many garden pests that will give your potato plants a hard time.  The potato beetle is one such pest.  The potato beetle, or Colorado potato beetle, has a yellow or orange body, along with stripes running along its back.  They are about a quarter to half an inch in length.

Colorado potato beetle
A potato beetle on a potato plant.

They can lay 500 eggs in a 5-week period, usually on the underside of a leaf.  They are possibly the biggest culprit in potato plant defoliation (eating and removal of the leaves).

Potato beetles have developed resistance to numerous pesticides over the years.  Crop rotation is one way to combat their spread.  Mulching potato plants with straw can also help to hide the potato plants for a time, and to encourage the potato beetle’s predators to protect your plants.

Conclusion

Hopefully, this article gave you enough information on how to plant sprouted potatoes, how to care for the plants, and how to harvest and store your bounty.  You should also have enough information to avoid some of the more common problems with growing potatoes.

I hope that you found the article helpful.  Please leave any questions, or potato-growing hints of your own, in the comments below.

For more information on growing potatoes, check out this article from Cornell University.

jonathon.david.madore

Hi, I'm Jonathon. I’m the gardening guy (not guru!) who is encouraging everyone to spend more time in the garden. I try to help solve common gardening problems so that you can get the best harvest every year!

Recent Content