How to Grow Potatoes

Guide Note Potatoes are one of the most widely used vegetables in the United States. However, the vegetable can be susceptible to a number of diseases and viruses. Knowing the proper method of how to grow potatoes is essential if you want to have a healthy and bountiful crop.

Table of Contents

• Introduction
• Types of Potatoes
• Soil Requirements
• Cutting and Handling Seed Potatoes
• How to Plant
• Potato Plant Care
• Dealing with Disease
• Dealing with Pests
• Harvesting and Storage
• Conclusion
• References

Growing Potatoes Tips

1. Potatoes come in a variety of colors, including red, yellow and blue.
2. Different varieties are good for different uses.
3. Planting certified seed potatoes will help minimize problems with disease.
4. Potatoes should not be grown in the same spot two years in a row.
5. Careful harvesting is necessary to avoid post-harvest diseases.

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Introduction

• The potato seems as American as apple pie and the bald eagle, but in reality it is grown around the world. While most people love to eat them, the potato has been used for other things such as powering clocks and embarrassing vice presidents.^{1 2} No matter what you want to use them for, nothing is more satisfying than using the potatoes you grew yourself.

Types of Potatoes

• With over 500 varieties of potato on the market, you may find it difficult to choose just one. Usually, you should choose a variety of potato that is well-suited for what you plan on using it for. Here are a few of the more common ones you will find on the market.

Early Season

• Frontier Russet: Early to medium-early season russet potato with white flesh and shallow eyes.
  1. Resistant to verticillium wilt, fusarium dry rot and common scab but susceptible to early blight.^{3 4}
  2. Excellent for french fries at harvest and good for baking.⁵
     

     The potato world extends further than just Russet and Rose. (Creative Commons photo by Curt Gibbs)
• Norgold Russet: Early season russet potato.
  1. Resistant to scab but susceptible to blackleg and hollow heart.^{3 6}
  2. Fair to good for baking and boiling.
• Norland, Red Norland and Dark Red Norland: Early season red skinned potato with white flesh and shallow eyes.
  1. Red Norland and Dark Red Norland are clones or mutations of Norland.⁷
  2. Highly resistant to scab; resistant to leafroll and potato viruses A and Y.⁸
  3. Excellent for boiling and frying; good for baking.⁹
• Russet Norkotah: Early season russet potato.
  1. Tuber physiological disorders are very rare even in dry conditions.⁶
  2. Highly resistant to common scab but very susceptible to verticillium wilt and blights.^{3 10}
• Superior: Early to midseason potato with white, white flesh and shallow eyes.
  1. Excellent for long storage.¹¹
  2. Excellent for chipping; okay for baking, boiling and frying.¹²
  3. Resistant to net necrosis and common scab; moderately resistant to internal heat necrosis; but susceptible to blackleg, fusarium, leafroll virus, verticillium wilt and some viruses.¹³

Midseason

• Goldrush: Midseason russet potato with shallow eyes.
  1. Very resistant to drought, common scab, black spot bruising, verticillium wilt and hollow heart but susceptible to most common potato viruses and other potato diseases.^{14 15}
  2. Excellent for baking and boiling.¹⁶
• Kennebec: Mid to late season potato with white skin and flesh and shallow eyes.
  1. Excellent for baking, boiling, chipping and frying.¹⁷
  2. Very susceptible to verticillium wilt, tuber greening and pinkeye.¹⁸
• Red Pontiac: Midseason red potato with deep eyes.
  1. Fair to good for most uses.¹⁹
  2. Tolerant to drought.²⁰
  3. Susceptible to most common potato diseases.²¹
• Yukon Gold: Mid to late season potato with yellow skin and flesh and medium-deep eyes.
  1. Yukon Gold has become very popular recently.²²
  2. Good for boiling, baking and french frying but not chipping.²³
  3. Resistant to mild mosaic and moderately resistant to the leafroll virus.²⁴

Late Season

• All Blue: Late season potato with blue to purple skin and flesh with medium to shallow eyes.
  1. Also known as Congo, Blue Marker, Russian Blue, British Columbia Blue, McIntosh Black, River John Blue and Sharon's Blue.²⁵
  2. Great for salads, baking and mashing; stores well.^{25 26}
• Butte: Late season russet potato with white flesh shallow eyes.
  1. Stores well.²⁷
  2. Resistant to late blight, common scab and tuber net necrosis caused by the leafroll virus.²⁸
• Katahdin: Late season potato with white skin and flesh and shallow eyes.
  1. Stores well.²⁹
  2. Susceptible to scab but resistant to moderately resistant to mild mosaic, net necrosis, brown rot. blackleg, verticillium wilt and some viruses.^{30 31}
• Russet Burbank: Late season russet potato with medium-deep eyes.
  1. The most popular cultivar grown in the United States.³²
  2. Excellent for baking and processing; stores well.³³
  3. Resistant to black leg and moderately resistant to common scab and fusarium dry rot.³⁴

Potato Variety Lists

• For more information about additional varieties of potatoes, check out one of the following lists:

1. NC State University: Vegetable Cultivar Descriptions for North America: Potato
2. Oregon State University: Variety Selection
3. Cornell University: Vegetable Varieties for Gardeners: Potatoes
4. Washington State University: Potato Varieties: A Comprehensive List  
5. Washington State University: Specialty Potatoes  
6. Potato Goodness.com: Potato Varieties Grown in the U.S.  

Soil Requirements

• Potatoes need a well-draining fertile soil to thrive and should not be grown in the same location each year. Wait at least three years before planting potatoes in a spot where they have previously been grown.³⁵

1. Potatoes do best with a pH level of 5.0 to 6.0.³⁶
2. Do not plant potatoes in areas with dry sands, shales or heavy clay loam soil.³⁵
3. Soil should be fertilized with a 05-10-10 fertilizer.³⁶
4. Do not over fertilize, which can encourage potato scab.³⁶

Cutting and Handling Seed Potatoes

• Potatoes are not true seeds, but are planted from stem tissue known as "tuber." You can purchase seed potatoes from your local garden center or through a mail order company.³⁵ Most seed potatoes will need to be cut and dried before planting.
  

  The sprouts and seed potatoes are more pleasant (and beneficial!) than the buds on the potato sitting at the back of your pantry. (Creative Commons photo by Nick Johnson)

1. Use certified seed potatoes. Certified seed is grown under strict guidelines and thoroughly inspected by state authorities.³⁵
   1. Do not use homegrown potatoes because they are likely heavily infested with viruses that will ruin your crop.⁶
   2. Supermarket potatoes cannot be used because they are usually treated with chemicals that permanently inhibit sprouting or may harbor diseases, even organically grown varieties.^{6 36}
   3. Certified seed is not guaranteed to be disease free, but rather will have a less percentage of disease.³⁷
   4. Bacterial ring rot, blackleg, common scab, late blight, potato viruses, powdery scab, Rhizoctonia, root knot nematodes, silver scurf and wilt diseases can all be carried through infected seed tubers.³⁷
2. Try to purchase your seed potatoes two to three weeks before you anticipate planting them so you can "sprout" them.³⁵
   1. Place the potatoes one layer deep in a warm (70°F) area with direct sunlight.³⁵
   2. Turn the potatoes to "green" the skin's surface and allow 1/4 to 1/2 inch long sprouts to form.^{35 36}
   3. This should cause your plants to emerge one to two weeks earlier.³⁵
3. Seed potatoes come in a variety of sizes. B-sized tubers weigh only an ounce or two and do not require cutting.³⁶ Simply plant each one as a single seed.³⁵
4. Larger seed potatoes should be cut into smaller pieces.
   1. Your ideal seed piece should block shaped, weigh between 1 to 2 ounces (about the size of a golf ball or ice cube) and have at least two "eyes" or buds on it.⁶
   2. Make the first cut lengthwise in order to divide the cluster of buds at the end of the potato.³⁵
   3. Cut the potato as little as possible.⁶
   4. Smaller-sized pieces can result in weaker plants and make them more vulnerable to late frost injuries.³⁵
   5. Each pound of seed potatoes should contain about eight to ten seed pieces.³⁵
5. Store the cut pieces for one to seven days before planting to allow the surface to dry and form a callus, which will decrease the chance of rot.³⁸
   1. Pieces should be stored at room temperature (60 to 70°F) in an area with high humidity and good ventilation.³⁵
   2. A closed (but not sealed) cardboard box with ventilation holes is an ideal location to store cut pieces.⁶ Pieces can be piled about 6 inches deep.
   3. Do not store pieces in an airtight container.⁶

How to Plant

• Once the seed potatoes have been properly prepared, you are ready to plant your potatoes.

When to Plant

1. Potatoes can be planted any time from from March until mid-June.⁶
2. The morning soil temperature should be at least 48 to 50 degrees F at a depth of 4 inches before planting.³⁵
3. Planting too early can cause seed pieces to rot.³⁹

You don't need acres of land to portion out adequate growing space. (Creative Commons photo by Lance Fisher)

Spacing

1. Rows should be spaced 2 to 4 feet apart.
   1. Wider rows allows for easier cultivation and hilling.⁶
   2. Closer rows allow the plants to shade the soil and prevent high soil temperatures which inhibit tuber growth.³⁹
2. Seeds should be spaced between 6 to 15 inches apart.
   1. Seed spacing depends on the variety of potato, depth of soil, soil fertility and moisture levels of the soil during the season.³⁵
   2. Allow more space between your seeds if you want larger potatoes; less space for smaller potatoes.⁶

Planting Tips

1. Till the soil about 6 to 8 inches deep before planting. Do not over till, which can cause the soil to seal over and lead to seed piece suffocation and death.⁶
2. Potatoes should be planted in furrows at a depth of about 2 to 4 inches.
   1. Shallow plantings will encourage a faster emergence.³⁵
   2. Deeper plantings are is acceptable in dry or sandy soils.⁶
3. Plant the cut side down with the eyes pointing up.³⁶
4. Rows should be slightly mounded to allow water to drain from the seed pieces and reduce decay.^{6 35}
5. If a late, severe frost is expected, protect young plants with a temporary covering of straw or newspaper.³⁵

Straw Potatoes

• A special method of growing potatoes that does not require cultivation or hilling is called "straw potatoes." This involves placing the seeds and rows the same way as listed below, but instead of burying the seeds they are covered with 4 to 6 inches of straw, cornstalks or other mulch type material.³⁵ This method is often used by gardeners who are growing potatoes for competition because the tubers are better shaped.³⁹

Potato Plant Care

• The two most important areas of potato plant care are cultivation and watering. Cultivation allows you to eliminate weeds, loosen the soil and hill the plants.

Cultivation, Hilling and Weed Control

• Cultivation will help break up the soil around your plants. This will get rid of weeds, help aerate the soil and allow you to ridge the row.³⁹ This process is known as "hilling" or "dirting." Hilling is done to cover areas of the stem so potatoes can develop.³⁵ It will also reduce the number of "sunburned" or green tubers.³⁹
  

  Dont let a weed infestation stifle your harvest. (Creative Commons photo by Bart)

1. Hilling should begin when plants are about 6 to 8 inches high.³⁵
   1. Mound the soil around the base of the plant to form a ridge.
   2. You can either leave a few of the upper leaves exposed or bury the entire plant under the soil.³⁶
   3. You will probably need to hill two to three times during the season to ensure that new tubers do not push out of the soil.³⁶
   4. By the time the plants are 15 to 18 inches tall, the ridge should be between 4 to 8 inches high and 10 to 12 inches across.^{35 6}
2. Cultivation should be at depths of less than 2 inches.³⁵
   1. Be careful when hoeing around potato plants as they can be easily damaged.³⁹ Cut tubers are more likely to develop disease and viruses.
   2. Stop cultivation and hilling after the plants have bloomed to avoid damaging the roots.⁶
3. Avoid using herbicides to control weeds. No herbicide can be used safely around all types of vegetables and are difficult to apply at proper rates in small areas.³⁵
4. Mulching is an effective measure for weed control around potato plants and will help conserve soil moisture while helping to maintain a uniform soil temperature.³⁵

Watering

• Proper moisture is essential to potato growth. The exact amount of water that potatoes need depends on soil type, temperature, wind and other factors.³⁵ However, on average they will need between 1.5 to 2 inches of water per week until just before harvesting.⁶

1. Do not water before plants emerge unless necessary. Wet soils can lead to seed decay.
2. Potatoes should be watered by mid-day so that the leaves dry before nightfall and avoid encouraging fungal and bacterial diseases.⁶
3. During dry weather, watering is essential when the vines are 6 to 8 inches tall and about two weeks before harvesting.³⁵
4. Regular watering will reduce knobbiness, second growths, cracking and hollow cavities in tubers.³⁵
5. Because roots do not penetrate more than 18 inches into the soil, you can generally will only need to water once a week.⁶ Sandy soils may need watering more often.
6. Avoid frequent, light waterings that wet the surface but leave the roots dry.⁶

Dealing with Disease

• Disease control has more to do with planting correctly and controlling insects since seed tubers and pests carry many of the diseases listed below.⁶ Potato disease can be broken down into three major categories: foliage diseases, tuber and stem disease and viruses. Only the more common diseases will be discussed here; however, links to information on less common varieties can be found under Other Diseases. Information on diseases that affect potatoes during storage is found under Harvesting and Storage.

Keep the blight off of this pristine, innocent foliage. (Creative Commons photo by Erik Moeller)

Foliage Diseases

• Foliage diseases generally affect the leaves of the potato plant, but may affect the tubers as well.

• Early Blight
  1. Early blight is caused by the fungus Alternaria solani. It very common and found in most areas.⁴⁰
  2. Symptoms appear on older foliage first. Leaves develop circular to angular dark brown lesions about 1/5 inch in diameter.⁴¹ Rings often form in the lesions to produce a pattern similar to a bulls-eye.
  3. Fungicide programs used to control late blight are usually effective against early blight.⁴²
  4. Late maturing cultivars are typically more resistant to early blight. Some highly susceptible cultivars include Red Norland, Norchip and Superior.⁴²

• Late Blight
  1. Late blight caused the Irish potato famine in the mid-nineteenth century and an epidemic in the 1840s in the United States.⁴³
  2. First appears as small pale to dark green water-soaked lesions that are irregular in shape and surrounded by yellowish tissue.⁴⁴
  3. Late blight lesions are more watery and spread down the petiole and the stem than early blight lesions.⁴⁵
  4. Development of late blight is favored by high moisture or humidity above 90 percent with moderate temperatures (50 to 80°F for periods of at least 8 to 10 hours).⁴⁶
  5. New strains introduced from Mexico in the 1990s have increased the severity of late blight on tomatoes and potatoes in the United States and Canada.⁴³
  6. Control of late blight is usually done with fungicides.⁴⁷
  7. You can find research publications, extension publications and recent publications from Michigan State University on potato diseases on its website. ^{48 49 50}
• Verticillium Wilt
  1. First signs are usually when the lower leaves on the vine turn yellow and wither.⁵¹ It can also cause chlorosis and discoloration of the vascular ring in both the stem and the tuber.⁴⁵
  2. Most potato varieties are not resistant to this disease, especially Kennebec.⁵²
  3. Verticillium can be controlled using clean seed, seed treatments and crop rotation.⁴⁵

Tuber and Stem Diseases

• Tuber and stem diseases can be more difficult to detect because their signs are not as noticeable. Often you won't be aware that there is a problem until after harvesting the potatoes. However, since many of these diseases can occur year after year, it is important to know what their signs and symptoms are in order to prevent it from occurring again.

• Bacterial Soft Rot and Blackleg
  1. Both caused by varieties of the bacterium Erwinia carotovora.
  2. Blackleg usually affects young plants that are planted in cool, wet soil.⁵³
  3. Soft rot occurs when bacteria enters the tuber through a wound or other point of entry.⁵⁴
  4. Controlling these diseases is done primarily by planting certified seed, controlling moisture, crop rotation and proper planting.^{35 52}

• Black Dot
  1. Black dot is caused by the fungus Colletotrichum coccodes' and is both tuberborne and soilborne.⁵⁵
  2. First appears as a yellowing and wilting of plants in the middle to late season.⁵⁶
  3. Seed-piece fungicides are not effective in controlling black dot.⁵⁵
  4. Black dot can also affect tomatoes, eggplants and peppers.

• Black Scurf and Rhizoctonia Canker
  1. Both diseases are caused by the soil fungus Rhizoctonia solani.
  2. Most noticeable signs are wilting plants or hard black crusty spots resembling dirt on the tubers that can't be washed off, called "scurf."^{52 57}
  3. Control can be achieved through seed treatments, crop rotations, using clean seed and soil fumigation.⁵⁸

• Common Scab
  1. Common scab is caused by Streptomyces scabies, which is present in almost all soils.⁵⁹
  2. Symptoms of common scab vary in extent and appearance but include some type of leisions.⁶⁰
  3. The disease is worse in alkaline soils and during droughts.³⁵
  4. Resistant potato varieties include Russet Norkotah or Goldrush; Moderately resistant varieties include Norland or Superior.⁵²

Viruses

• Viruses can infect potatoes and cause numerous problems such as leaf or tuber malformations, growth problems and reduce yield.⁶¹ You can greatly reduce the chances of viruses by planting only certified seed and controlling insects.³⁵ The most common virus that affect potatoes include:
  1. Leafroll⁶²
  2. Mosaic Diseases Caused by Potyviruses⁶³
  3. Potato Virus Y (PVY)⁶⁴
  4. Potato Virus Y (PVY)⁶⁴

Other Diseases

• Potatoes can be susceptible to a few other disease not listed above, although they are less common. These diseases include:

Dealing with Pests

• Although there are several different types of pests that can attack potatoes, only one or two insecticides are necessary to control almost all of them.⁶ Often you can control them with insecticidal soap.³⁸ Mesh row covers are another method of controlling insects, but are expensive and inconvenient to use. If you do use insecticides, spray them early or late in the day when bees are less active since most insecticides are toxic to honeybees.⁶

Aphids

• Aphids are small soft-bodied insects that suck the sap out of plant leaves and stems. They come in various colors but are usually green, pink or gray and may or may not have wings.

1. Aphids often carry viral diseases.
2. Green peach aphids and potato aphids are the two most common varieties found on potatoes.⁸⁰
3. Aphids cluster on the undersides of leaves and shoot tips.⁶
4. Vines of infested plants often become covered with a thick, sticky honey dew that is excreted by aphids.⁶

Legions of multi-legged pests are waiting for you to let your guard down, even for a second. (Creative Commons photo by Ishikawa Ken)

Colorado Potato Beetles

• The Colorado potato beetle is a black and yellow striped round beetle that lays rows of orange eggs on the underside of potato leaves.³⁵

1. Both adults and larvae will chew on the leaves of the plant.⁶
2. Crop rotation helps reduce Colorado potato beetle populations.³⁵

Flea Beetles

• Flea beetles are very small (1/16 inch) black beetles that can leave holes or white streaks on leaves in the late spring.³⁹

1. They will also attack cabbages, eggplants, radishes, spinach, sweet corn and turnips.
2. Severe cases can kill off leave and decrease your yield.³⁹
3. Good sanitation around your garden will help control flea beetles.³⁵
4. Special controls for flea beetles is rarely necessary since damage is not usually noticed until after harvest.⁸¹

Leafhoppers

• Leafhoppers (also known as beet leafhoppers) are green, wedge-shaped insects about 1/10 to 3/8 inch long.

1. Symptoms of infestation include curled or crinkled foliage and "hopper burn," which turns the edge of the leaves brown.³⁹ Older leaves will be affected first.³⁵
2. They also attack beans, carrots, cucumbers and muskmelons.
3. Leafhoppers spread the curly top virus.⁸²
4. Insecticides used to control aphids and flea beetles will also control leafhoppers.⁸²

Wireworms

• Wireworms are thin brown hard-bodied worms that can grow up to 1-1/2 inches long.

1. The larvae bore deep funnel-shaped holes into the potato.
2. More common in gardens that were used as a waste area or pasture areas full of grass, clover or weedy alfalfa.^{35 83}
3. Granular insecticides can be used to control wireworms, but you may need to rotate crops or move the whole garden to get rid of them.⁶
4. You can detect wireworms by baiting: place carrots or untreated corn about 4 to 6 inches into the soil when the soil temperature is 50°F.⁸³

Other Pests

• Some of the other pests that can be found on potatoes, although less often, include:

Harvesting and Storage

• 

  It's time to dig into some pay dirt! (Creative Commons photo by Till Westermayer)
  You will know that your potatoes are ready to harvest when the leaves yellow and the foliage starts to die back. This will occur about 70 to 100 days after planting, depending on the variety.³⁶

1. In order to reduce peeling, bruising and rot during storage, do not dig up the potatoes until two weeks after the vines have naturally died down.⁸⁸ Do not water during this time.³⁶
2. If the skin is thin and rubs off easily, the potatoes are not ready to harvest.³⁶
3. Use a shovel or spading fork to dig out the potatoes, which are growing about 4 to 6 inches below the soil's surface.³⁹ Be careful not to bruise or cut into the potatoes.
4. If harvesting when temperatures are above 80°F, place potatoes into a dark area immediately to prevent them from turning green or rotting.⁸⁸
5. If you want to store potatoes for longer than six weeks, you need to cure the potatoes.
   1. Curing is done by placing the potatoes in a dark place with a temperature between 60 to 65°F and a humidity level above 85 percent for 10 to 14 days.⁸⁸
   2. After potatoes are cured, toss out any potatoes that are soft and shriveld.³⁶ Then, store them in a cool (40 to 45°F) dark place with high humidity.⁸⁸

Post Harvest Diseases

• Potatoes are susceptible to a number of post harvest diseases that are usually caused by fungii.⁸⁹ These disease are often present before the potatoes are harvested but do not show the signs until after the harvest. You can avoid most problems with post harvest disease by allowing the potatoes to stay in the ground before harvesting, planting disease free seed, following good rotation practices, and storing potatoes at low temperatures.^{88 89}

• Some of the most common post harvest diseases include:

1. Fusarium dry rot⁹⁰
2. Tuber late blight⁹¹
3. Silver scurf⁹²
4. Pink rot⁹³

Conclusion

• Now that you have your homegrown potatoes, it is time to decide how you want to eat them. Your choices are numerous: potato salad, french fries, mashed potatoes, au gratin potatoes, scalloped potatoes, twice baked potatoes, baked potatoes and potato chips. Of course, if you're not sure how to make one of those items, check out some of Mahalo's How To pages like How to Make Potato Salad, How to Make Potato Chips, How to Bake a Potato, How to Make Mashed Potatoes and How to Microwave a Potato.

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References for How to Grow Potatoes

1. ↑ About.com: Potato Clock - Make a Potato Battery to Power an LED Clock
2. ↑ Capital Century: 1992: Gaffe with an 'e' at the End
3. ↑ ^{3.0 3.1 3.2} NC University: Vegetable Cultivar Descriptions for North America: Potato
4. ↑ The Potato Association of America: Frontier Russet
5. ↑ Canada Food Inspection Agency: Frontier Russet
6. ↑ ^{6.00 6.01 6.02 6.03 6.04 6.05 6.06 6.07 6.08 6.09 6.10 6.11 6.12 6.13 6.14 6.15 6.16 6.17 6.18 6.19 6.20 6.21 6.22 6.23 6.24 6.25 6.26 6.27 6.28} Oregon State University: Grow your Own Potatoes
7. ↑ University of Nebraska–Lincoln: Norland: Characteristics
8. ↑ Cornell University: 'Dark Red Norland' Potatoes
9. ↑ The Potato Association of America: Norland
10. ↑ University of Nebraska–Lincoln: Russet Norkotah: Characteristics
11. ↑ Cornell University: 'Superior' Potatoes
12. ↑ Canada Food Inspection Agency: Superior
13. ↑ The Potato Association of America: Superior
14. ↑ Cornell University: 'Gold Rush' Potatoes
15. ↑ The Potato Association of America: Goldrush
16. ↑ Canada Food Inspection Agency: Goldrush
17. ↑ Canada Food Inspection Agency: Kennebec
18. ↑ The Potato Association of America: Kennebec
19. ↑ Canada Food Inspection Agency: Red Pontiac
20. ↑ Cornell University: 'Red Pontiac' Potatoes
21. ↑ The Potato Association of America: Red Pontiac
22. ↑ University of Nebraska–Lincoln: Yukon Gold: Characteristics
23. ↑ Canada Food Inspection Agency: Yukon Gold
24. ↑ The Potato Association of America: Yukon Gold
25. ↑ ^{25.0 25.1} Tucker Farms: All Blue
26. ↑ Cornell University: 'All Blue' Potatoes
27. ↑ Cornell University: 'Butte' Potatoes
28. ↑ Canada Food Inspection Agency: Butte
29. ↑ Cornell University: 'Katahdin' Potatoes
30. ↑ The Potato Association of America: Katahdin
31. ↑ Canada Food Inspection Agency: Katahdin
32. ↑ University of Nebraska–Lincoln: Russet Burbank: Characteristics
33. ↑ The Potato Association of America: Russet Burbank
34. ↑ Canada Food Inspection Agency: Russet Burbank
35. ↑ ^{35.00 35.01 35.02 35.03 35.04 35.05 35.06 35.07 35.08 35.09 35.10 35.11 35.12 35.13 35.14 35.15 35.16 35.17 35.18 35.19 35.20 35.21 35.22 35.23 35.24 35.25 35.26 35.27 35.28 35.29 35.30 35.31 35.32 35.33 35.34 35.35 35.36 35.37} Penn State College of Agricultural Sciences: Growing Potatoes  
36. ↑ ^{36.00 36.01 36.02 36.03 36.04 36.05 36.06 36.07 36.08 36.09 36.10 36.11 36.12} DIY Network: Selecting and Growing Potatoes    
37. ↑ ^{37.0 37.1} UC IPM Onlne: Seed Certification and Seed Tuber Handling
38. ↑ ^{38.0 38.1} UC Davis: Potato, white  
39. ↑ ^{39.0 39.1 39.2 39.3 39.4 39.5 39.6 39.7 39.8 39.9} University of Illinois Extension: Watch Your Garden Grow: Potato
40. ↑ Vegetable MD Online: Potato Early Blight (Alternaria solani Sorauer)
41. ↑ UC IPM Onlne: Early Blight
42. ↑ ^{42.0 42.1} Michigan State University: Early Blight
43. ↑ ^{43.0 43.1} Vegetable MD Online: Late Blight of Potatoes and Tomatoes
44. ↑ UC IPM Online: Late Blight
45. ↑ ^{45.0 45.1 45.2 45.3} Michigan State University: Foliar Diseases/Conditions of Potato
46. ↑ Vegetable MD Online: Potato Late Blight (Phytophthora infestans)
47. ↑ Vegetable MD Online: Late Blight Concerns for Potatoes in 2003
48. ↑ Michigan State University: Research Publications
49. ↑ Michigan State University: Extension Publications
50. ↑ Michigan State University: Recent Publications
51. ↑ UC IPM Online: Verticillium Wilt
52. ↑ ^{52.0 52.1 52.2 52.3} North Dakota State University: Management Of Potato Diseases in the Home Garden
53. ↑ UC IPM Online: Bacterial Soft Rot and Blackleg