Growing Potatoes

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These Irish potatoes grow in rows. As the plants grow taller, you should cover the stem with soil, which is called hilling.

These potatoes are growing in rows. Above ground, the plants reach about 2 feet tall. Cover the lower stem with soil, called “hilling,” to prevent greening of the tubers below ground.

An ancient vegetable, potatoes were first cultivated by the ancient Incas in Peru. This crop came to America in 1621, and today is the most popular vegetable in the United States. If you love potatoes and have never tasted a homegrown one, you definitely need to try growing potatoes. Potatoes are cool-season vegetables and yield the best quality and number of tubers in the northern portion of the country. And just so you know: A potato isn’t a root but an underground storage stem called a tuber.

Note: While we do not currently carry this variety, we offer this information for gardeners who wish to grow it.

Soil, Planting, and Care

Plants produce potatoes of various shapes and sizes.

Shapes and sizes of homegrown potatoes will vary even from the same plant.

Potatoes are cool-season crops and can survive light frosts. Plant as soon as soil is workable in early spring. Potatoes need fertile, well-drained soil that’s loose and slightly acid (pH 5.8 to 6.5). Hard, compacted soil produces misshapen tubers. Amend heavy clay soil the fall before planting by working organic matter into planting beds. Potatoes form tubers 4 to 6 inches below the soil surface. When stems reach 8 inches tall, draw soil up and around plants, covering half of lower stems. Repeat the process two to three weeks later. Potatoes exposed to sunlight turn green, which causes flesh to taste bitter. Keeping tubers covered prevents greening.

Some gardeners grow their potatoes in straw, placing straw around the 8-inch-tall stems instead of soil. This method yields potatoes that you don’t have to dig, but simply fish out of the straw. If you use the straw method, be sure to keep your straw layer consistent throughout the growing season. It will most likely break down and need to be topped off during the course of growing the potatoes.

Instead of hilling potatoes, some gardeners use layers of straw to cover the stem.

Rather than hilling these potato plants with soil, gardeners at the Wishard Slow Food Garden in Indianapolis layered straw around the plant stems.

Maximum tuber formation occurs when soil temperature is 60 F to 70 F. Tuber formation stops when soil temperature hits 80 F. Mulching soil with straw or other organic matter can help reduce soil temperature. Research has shown that maintaining a 6-inch-thick straw layer around potatoes keeps soil temperatures 10 degrees lower. Potatoes are sensitive to drought. Keep plants consistently moist, especially when plants flower and right after, since this is the peak time when tubers are forming.

Move potatoes to a different place in the garden each year to help limit disease and insect problems. For best success, rotate potatoes on a 3-year program, growing them in a different spot for three years in a row before cycling through the growing spots again.

Troubleshooting

Potato plants produce flowers as the tubers are growing underground.

This potato plant is flowering, which indicates that the tubers are forming underground. Keep plants well watered during and after flowering.

Potatoes will develop areas of green skin when they’re exposed to direct sunlight during growth. The green areas have a bitter taste because the flesh contains a moderately poisonous compound. When preparing potatoes, cut away any green areas and discard. Potatoes in storage will develop green spots if they’re exposed to sunlight or fluorescent light. Keep stored potatoes in darkness. If your storage space isn’t completely dark, store potatoes in a box with a lid. Mounding soil or straw around potato stems will protect developing tubers during the growing season. Wedge-shaped leafhoppers feed on potato leaves, causing them to curl or crinkle and edges to turn brown. Flea beetles, which are tiny (1/16 inch), black, and shiny, create white streaks in leaves or small holes. They typically infest plants in late spring. If the infestation is bad enough, it can cause some leaves to die, which will reduce yield. Colorado potato beetles can also ravage plants. Read more about all of these pests and their control in our Pest Identification section.

Harvest and Storage

New potatoes are potatoes that have been harvested early. These are red new potatoes.

These red potatoes were dug early as “new” potatoes. New potatoes have thinner skin and are typically eaten unpeeled.

You can harvest new potatoes usually about two to three weeks after plants flower. If soil is loose enough, dig potatoes free with your hands. Otherwise, use a shovel or digging or spading fork to loosen soil near stems.Harvest all potatoes after vines have died. If the growing season has been rainy, wait a few days for soil to dry. It’s easier to dig potatoes in dry soil. You’ll find tubers 4 to 6 inches below the soil surface. Use a shovel or digging or spading fork, inserting the tool 6 to 10 inches away from the plant stem. Loosen and pry up soil gently, looking and feeling around for tubers.

Brush dry soil from potatoes. Don’t wash them if you plan to store them. Newly dug potatoes don’t have a tough skin. Handle tubers gently to avoid damaging and bruising them. Curing produces a tougher skin. To cure potatoes, place in a humid spot at roughly 55 F for two weeks.

Wait until soil is dry to dig potatoes.

It’s best to dig potatoes when the soil is dry.

If you plan to store potatoes into winter, select tubers that are firm and without soft spots. Store in a dark room with high humidity; the temperature should be 38 F to 40 F. Do not store potatoes with apples. Check potatoes frequently for sprout formation; knock off sprouts with your hands and dispose. Do not refrigerate potatoes. Tubers will hold at room temperature for 1 to 2 weeks.

Uses

Use new potatoes with creamed peas, to make soup, or to roast, seasoning with parsley and butter. Prepare mature potatoes in any way you desire. Remember to place peeled or cut potatoes in water to prevent discoloration. Great herb partners for potatoes include dill, fennel, cilantro, basil, chives, parsley, oregano, rosemary, sage, and thyme.

24 thoughts on “Growing Potatoes

  1. my potatoes were doing great then this morning while checking for beetles i noticed the stems likebreak like something ate it. any suggestions what it might be and how to treat

    • Hi Angi,
      A couple of possibilities come to mind from your description. One is cutworms. There is a picture of cutworm damage to Irish potatoes (and control) in this publication from the Univeristy of Minnesota. I would make collars for the plants to protect them if you think you may have had a run in with cutworms. Secondly, if it has rained a lot and the soil is not well draining, stems may rot at the soil line. You would notice the black discoloration in the stem. – danielle, Bonnie Plants

  2. planted burpless cucmbers 3 weeks ago the leaves are turning white around leaves edges. why is this happening?

    • Hello Jere,
      Have you had any cold nights that could have led to cold burn (or wind burn) on the plants? It is typical of cucumbers and other members of the cucurbit family. -danielle, Bonnie Plants

  3. we planted our potatoes back in febuary an they were looking great we had a small freeze now for two days in a row one day i didn’t cover them an it got down to 30 degrees an last night we did cover them an it was 26 degrees will this freeze kill my plants or should they be ok first year to plant potatos

    • Hi Wiley,
      While Irish potatoes thrive in the cool weather, sometimes a hard freeze is tough. There may be plenty of underground tissue to regenerate if the foliage is knocked back. Have you checked the potatoes? Is the foliage healthy?
      -Danielle, Bonnie Plants

      • i have checked them only on what they look like above ground the foiliage is very soft not crisp like it was before the freeze we planted red potatoes will the foiliage come back or should we replant

        • Hi Wiley,
          A late hard freeze in Spring can knock the above ground part of Irish potatoes to the ground; and they can recover. I am not sure where you are located, so it is hard to say if you should replant. Give it a few days to check for new growth. Good Luck!
          -Danielle, Bonnie Plants

          • we live in texas an it did knock them back but they have started to come back so i think they are going to be ok thanks so much for all your help

  4. What combination of fertilizer should I use to get big, smooth red potatoes ?

    • Hi Earl,
      Potatoes are moderate feeders. You will want to avoid using too much processed manures since it can cause scabby areas on potatoes. While most veggies prefer a soil pH of 6.5 or so, potatoes are much more comfortable growing in a soil with a pH around 5.5. The combination of fertilizer used for Irish potatoes depends on what is available in your soil. I usually soil test every 3 years and go by the results until I have another one ran. You can do that through your local extension system. This is a great publication on growing Irish potatoes in the home garden from the Univeristy of Arkansas extension with more specifics.
      -Danielle, Bonnie Plants

  5. I just built a square box out of pallets and was hoping to grow potatoes inside any suggestions on how I should layer the soil & compost, how deep should it be.. anybody?

    • Hi Jen,
      Use a very loose soil or compost mix. Irish potatoes have been grown in rotted leaves and even sawdust. Fill the bin about 5 or 6 inches and plant the Irish potatoes. When the potato foliage grows through the soil mix a couple of inches, add soil to the Irish potato foliage. Keep repeating this until the Irish potatoes are ready for harvest! Check out this article from Mother Earth News about growing Irish potatoes in a barrel. Gardeners are getting very creative.
      Happy Gardening,
      Danielle

    • Hi pjp,
      You can grow potatoes in a container, though you might want a larger container for a bigger harvest. This article from the Wisconsin Journal Times shows you how. You might also enjoy growing in straw piles or straw bales, as harvesting is easy. ~Mary Beth, Bonnie Plants

  6. To keep deer out of your garden mix up powdered milk as directed and spray on anything the deer or rabits eat. They will leave all the sprayed stuff alone

  7. Can red potatoes be grown in a wire container using straw and soil -layering them on each other?

    • Hi Lauren,
      Growing potatoes in layers of hay or straw makes harvesting much easier. This article from Colorado State Extension gives another tip on using garbage cans. This article discusses growing in straw as well. The wire simple allows for you to keep it contained in your garden space, but isn’t necessary. Let us know how it grows! ~Mary Beth, Bonnie Plants

  8. I am a first time “gardener” and I planted store bought red potatoes. I was told to wait until the plant dies until I try to harvest and just read your information above. I saw a few flowers weeks ago. Should I go ahead and harvest the potatoes? I know there is at least 1 because I dug carefully out of curiosity and saw it. Also, the plant itself is leaning so far over it is almost laying on the ground. It’s not dead, only a few yellow leaves, but leaning over? Should I do anything?

    • Hi Deborah,

      If you want small red potatoes, often called “new potatoes,” you should harvest a few weeks after the plant flowers, but to harvest larger, full-size potatoes, you can wait until the plant dies back. It just depends on what you prefer. Also, I think it’s fine that your plant is leaning. Happy growing!

      Kelly, Bonnie Plants

  9. We planted store potatoes before I found your website, and we did get quite a few potatoes from them. But since they were from store bought potatoes should I throw them away?Or are they safe to eat ? And are they ok to plant the small ones again as seeds? Or should I just toss them all? (They look fine to me just alot of small ones). Thanks for your help.

    • Hi Tracie,

      So you planted from potatoes bought at the grocery store? I can’t really tell you whether the potatoes you planted are safe to eat. They are probably just fine, but it depends on whether you want an organic or non-GMO source or are okay with anything. But if you’re comfortable with them and they produce for you, by all means, go for it!

      Kelly, Bonnie Plants

  10. thanks for the straw hilling tip. i have a hard time hilling with soil.
    what happens if deer have eaten the leaves off the potato plants? are they lost, or will they sprout again?

    • Hi Chantal,

      Potato plant leaves capture sunlight to promote growth, including root growth, so if your plants lose all their leaves to deer, the potatoes underground will certainly suffer. Have the deer eaten all the leaves? Some leaves should grow back, so your plants may still produce potatoes. But you’ll need to address the problem of deer eating your plants so they don’t mow the potatoes down again! Read the article Keeping Out Deer from our friend P. Allen Smith for some ideas on protecting plants from deer.

      Kelly, Bonnie Plants

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