Purple potatoes also known as blue potatoes are colored-flesh and skin potatoes rich in anthocyanins and carotenoids. Pigmentation is the primary differentiator between purple potatoes and regular potatoes. Anthocyanins are the water soluble flavonoid in purple potatoes responsible for the purple pigment. Anthocyanins carry a range of health benefits. Purple potato varieties include All Blue, Blackberry, Congo, Purple Fiesta and Purple Majesty among others. Depending on variety, purple potatoes mature in 70 to 130 days from planting. Many cultivars grow as early, mid-season or late-season varieties.
Table of Contents
Introduction
The botanical name of purple potato is Solanum tuberosum. North Carolina University Cooperative Extension notes that Solanum tuberosum encompasses many potato varieties of assorted textures, sizes, and colors. This affirms the fact that although potatoes may vary in type including color and pigmentation, botanically they are the same genus. There are altogether an estimated 10000 potato varieties grown across the world.
Apart from the purple potato, there are also other pigmented potato cultivars such as the yellow potato and the red potato. New purple potato hybrids join the growing list of dark pigmented vegetables such as purple tomato and red cabbage.
Dark pigmented potatoes are particularly interesting to researchers, nutritionists and dieticians because of their confirmed health benefits. On the other hand, agricultural scientists are especially interested in disease resistance offered by pigmented potatoes. Also interested in colored-flesh potatoes are culinary experts and home cooks who are finding new and exciting applications of pigmented potatoes in everyday food preparations.
Overall, potatoes are the most consumed vegetable in the United States. This makes the purple potato an attractive candidate for advancing the respective agendas of the many interested parties.
This feature provides an in-depth overview of the purple potato, namely, its origins, varieties, health benefits, culinary applications and how it can be grown in the home garden.
Purple Potato Origins
According to the University of Wisconsin USDA Agricultural Research Service, some 6000 years ago, native peoples of Central Andes, an area now known to be southern Peru and northern Bolivia, began domesticating certain wild potato species for human consumption. The potato history is lengthy. Over the years, books have been written exploring the history of potatoes.
The purple potato, in particular, is thought to be native to the Lake Titicaca region within the high plains and mountain slopes of Peru and Bolivia. Potatoes have a long history in the region. There is even a special research organization in Lima created in 1971, the International Potato Center, which is dedicated to the study and advancement of potatoes.
According to Specialty Produce out of San Diego, CA, purple potato introduction to the United States is as recent as the mid-1980s. This makes the United States a relative newcomer to the purple potato movement. The purple potato variety first gained popularity in California.
Whereas purple potatoes have become popular in recent years in North America, purple heirloom potatoes such as the Papa Púrpura have been a staple in Peru over many generations.
The continued rise of interest in purple potatoes in the US has been driven by newly developed varieties sponsored by the USDA, Universities and other research institutions (see our purple potatoes varieties section below).
Furthermore, the potential positive impact of the purple potato on human health in an increasingly health conscious society, has played its part in contributing to the intense interest surrounding coloured-flesh potatoes. Today, Universities and private companies are working hand-in-glove to make purple potatoes and other pigmented potato cultivars mainstream.
Purple Potato Characteristics
Characteristics of purple potatoes will vary with the cultivar considered. Heirloom potatoes tend to present significant differences from modern developed varieties. For example, the heirloom Papa púrpura or Peruvian purple potato has a deep purple skin and flesh. It is not necessarily a smooth skin potato, has bumps and unattractive deep eyes in addition to being bulky. When cooked the potato even turns bluish in color.
On the other hand, the modern purple potato, the Purple Fiesta for example, is a long and thin potato with a smooth purple skin and dark-purple flesh. It is bred to bring a certain special appeal to the market and also to resist certain problematic potato diseases. Thus the modern purple potato tuber is purposefully designed instead.
According to Dan Chin the holder of an exclusive license to grow and sublicense the Purple Fiesta seed in the United States, “These varieties were carefully bred to enhance all the unique qualities found in a colorful potato, including uniform size, striking color, rich vitamin and mineral content, sweet flavor, and versatility.“
This statement confirms that the modern purple potato is purposefully bred to be of exceptional appeal.
Regardless, purple potatoes, modern or heirloom, share a certain aspect in common, which is the purple or dark blue color they are well identified with. The following table lists some general characteristics of purple potatoes across cultivars.
| Item | Description |
| Skin | Purple, dark blue |
| Flesh | Deep purple, deep blue, white streaks |
| Shape | Elongated, oblong, round, fingerling |
| Diameter | 10-15cm or 4 to 6 inches |
| Flavor | Earthy, sweet |
| Days to Maturity | Up to 120 days |
| # of Varieties | > 10 |
Why Purple Potatoes are Purple
One of the most frequently asked questions is why are purple potatoes purple. Purple potatoes are purple for the same reason as blueberries, purple tomatoes and purple sweet potatoes. The reason is anthocyanins. Anthocyanins are naturally occurring water soluble pigments that are also known as flavonoids. Anthocyanins produce certain pigmentation in fruits, flowers and vegetables namely blue, red, or purple color.
According to a study published in the Food and Nutrition Research (2017), plant conditions determine pigmentation in fruits, vegetables and flowers. At low pH (less than 7.0) which translates to acidity, anthocyanins are red. At basic pH or alkaline conditions i.e. pH above 7.0, anthocyanins produce purple and blue pigmentation depending on actual pH level within this range.
In addition, another study that appeared in the International Journal of Food Sciences and Nutrition (2013) states that purple potatoes have a 20 fold anthocyanin concentration level than yellow potatoes. This is significant and of great importance to the success and appeal of purple potatoes (see section on health benefits).
In summary, purple potato tubers derive their purple color from anthocyanins. Anthocyanin pigmentation depends on acidity conditions in the potato. Potato tubers are alkaline, this causes anthocyanins to turn purple or blue as pH conditions change. This experiment on the purple potato pH palette provides some insights on the behavior of potato pigmentation.
Varieties Summary (Table)
The following table is a summary of some of the prominent purple potatoes. Each of the potato varieties on this table is considered in expanded detail in the next section.
| Pic | Name | Type | Date | Origin |
 | Blackberry | Hybrid | 2019 | Michigan, USA |
 | Purple Peruvian | Heirloom | 800yrs | Peru |
 | Purple Majesty | Hybrid | 1994/2005 | Colorado, USA |
 | All Blue | Heirloom | – | USA/Scotland |
 | Adirondack Blue | Hybrid | 2003 | New York, USA |
 | Purple Fiesta | Hybrid | 2014 | Prosser Washington USA |
 | Vitelotte | Heirloom | 800yrs | Peru |
Purple Potato Varieties in Detail
There are at least a dozen purple potato varieties. More continue to be developed. The varieties consist of heirloom varieties that have been passed down generations and bred cultivars that have been developed over the last few decades. In the United States, purple potato cultivars are a result of breeding rather than genetic modification. This makes many of them non-GMO. The following are some of the well known purple potato varieties.
Blackberry Purple Potato
The Blackberry purple potato is a small round spud that fits in the hand. It has deep purple flesh interior and deep purple skin due to a high level of anthocyanins. Furthermore, the potato offers disease resistance to the dreaded potato scab which is caused by the bacterium Streptomyces scabies.
Blackberry potato is a modern purple potato variety which was bred by David Douches at Michigan State University (MSU) Potato Breeding and Genetics Program. It is not a GMO but was developed over a period of 20 years involving conventional breeding, crossing and selection (see video). The purple potato has been used to process purple potato chips which are now available in grocery stores in the Great Lakes region, MI.
Blackberry Purple Potato (Video)
In this video, David Douches of Michigan State University (MSU) Potato Breeding and Genetics Program introduces the Blackberry purple potato giving its full features. He also provides insights into the commercial partnership to produce purple potato chips using the Blackberry.
Purple Peruvian Potato
Also known as Papa púrpura in Peruvian, the Purple Peruvian potato is an heirloom potato that is grown in Peru where it is a staple and available in local farmer’s markets.
The Papa púrpura is a fingerling which is elongated in shape and has many eyes on it that appear as depressions. For this reason, it may not be necessarily appealing to behold to the same level as the modern Blackberry or the Purple Fiesta varieties, for example. Furthermore, the Papa púrpura resembles wild roots, its skin is thin and does not require any peeling before use. When cut open, the flesh has blue and white patterns.
The Purple Peruvian potato matures in 110 days when planted. The potato is generally bigger than the modern varieties developed in the United States. Some home growers who have produced smaller sizes of the Papa púrpura at first, report having to first acclimatize the potato to local conditions in order to achieve bigger sizes. This is done by growing this purple potato over many seasons.
In the United States, we have found organic seeds of this purple potato stocked by Hudson Valley Seed Co.
Purple Majesty Potato
The Purple Majesty potato is a cross between the All Blue purple potato (another purple potato) and a white potato suitable for making chips. This resultant purple-flesh variety is darker than the All Blue.
The Purple Majesty has smooth looking purple skin resembling a medium sized smooth pebble as found on a river bed. When cooked, the potato resembles a nice looking lavender pigmentation.
Purple Majesty was developed by Dr. David Holm of Colorado State University San Luis Valley Research Center in southern Colorado. It was produced using conventional breeding methods in 1994 after about a decade of research work. The variety was introduced to the market in 2005. It is a non-GMO release.
According to a report carried in the Potato Grower, San Luis Valley Research Center produced crossbred varieties are tested for at least 8 years before “going to growers to provide feedback and possible use in commercial applications.” This suggests a non-GMO rigorous development process.
For growers, Purple Majesty has yield potential of nearly 500 sacks per acre of land utilized. In addition, the Purple Majesty is an early-maturing potato which is ready for harvest in 85 to 90 days.
All Blue Potato
The All Blue is susceptible to identification confusion due to an endless list of alternative names that points to the same potato. For example, by its other names it is called the Russian Blue, Nova Scotia Blue, Himalayan Black, Eureka Purple, Purple Congo or Congo Black among many other names.
Add to this, there is little clarity to its origins although some lean on the United States or Scotland. Nonetheless, the main characteristics of the All Blue include oblong or long cylindrical tubers, deep purple skin, purple flesh with white vascular rings and many evenly distributed deep eyes.
All Blue is used in the making of Terra Blues exotic vegetable chips which are sold via Amazon.
The All Blue purple potato is a drought tolerant purple variety which however struggles to achieve similar yields as it does in drought conditions during wet seasons.
Adirondack Blue Potato
Adirondack Blue is a purple potato with purple tubers. It has purple flesh and purple colored slightly netted skin. The tubers are oblong or elongated in shape and have some sunken eyes.
The potato variety was released in 2003 by the New York State College of Agriculture and Life Sciences at Cornell University. Adirondack Blue is a non-GMO potato which was crossed in 1993 (released in 2003) using the heirloom All Blue and Chieftain (a red potato) as the female. It has days to maturity of only 87 days from planting to harvest.
For best results, Adirondack Blue tubers should be harvested two weeks after vine killing. According to University of Florida IFAS Extension, vine killing results in uniform development of skin set and better maturation of the tubers. Furthermore, potatoes harvested following vine killing maintain better skin color, lose less weight in storage in addition to developing resistance to abrasion, according to IFAS Extension.
Although a crossbred, Adirondack Blue is susceptible to common scab, silver scurf, and the golden cyst nematode diseases. Nevertheless, the potato is flavorful and is used in mashes, salads and for roasting.
Purple Fiesta Potato
Stephen Ausmus
Purple Fiesta which you may also find labeled as Purple Pelisse, is a fingerling specialty purple potato. It is a small dark purple flesh and a smooth purple skin potato that fits into the palm of the hand. According to Dan Chin, a holder of the exclusive license to grow and sublicense the seed, “Purple Fiesta has ranked better in taste, color, and nutrition than any other blue or purple potato I’ve explored.”
The Purple Fiesta was bred by the Vegetable and Forage Crops Production Research Unit at the Agricultural Research Service scientists. Like most conventionally bred pigmented potato varieties, the Purple Fiesta was decades in the making. It was released in 2014.
The potato is suited for baking, roasting, microwaving, steaming, and mashing. The developers of Purple Fiesta further note that the variety was created to enhance certain unique qualities of coloured-flesh potatoes such as “uniform size, striking color, rich vitamin and mineral content, sweet flavor, and versatility“.
Just like its other purple competitors, the Purple Fiesta is also used in making chips and fries.
Vitelotte Potato
The Vitelotte is an heirloom purple potato. Although often suggested to have originated in France, Specialty Produce presents a different view. Vitelotte originated in ancient Peru 800 years ago. It is said to have only arrived in France in the 19th Century where it was first called Vitelotte Noir. Today its other names are Truffe de Chine, Négresse, Chinese Truffle, and Black Truffle.
This purple potato has a cylindrical fingerling looking shape. In typical heirloom fashion, it has frequently occurring eyes all over its skin along with irregular lumps. Furthermore, it has a deep purple skin which can also be observed as violet-blue in some varieties. The flesh of the potato has been described as “artistic purple” in some circles due to the purple hue marbled with white when cut open.
Vitelotte is good for baking, boiling, frying and steaming. Its flavor is nutty.
Purple Potato Health Benefits
Purple potatoes have been linked to a range of health benefits such as decreased oxidative stress, inflammation, improved immune status and blood pressure regulation.
The value of purple potatoes has been anchored in these health benefits. This has naturally drawn the interest of nutritionists, dieticians and a generally wide range of medical scientists. For example, the developers of the Purple Fiesta state that, among other things, they sought to breed a potato that had “rich vitamin and mineral content“. There is a clear human health benefit intention in the breeding.
Overall, the health benefits of purple potatoes are firmly hitched in the earlier discussed anthocyanins found in coloured-flesh potatoes. Science has long established that anthocyanins are beneficial to human health.
However, the intrigue with purple potatoes is the concentrated level of the anthocyanins in these potatoes. Purple potatoes enable high levels of anthocyanins to be consumed in a single sitting from a popular vegetable. This is a twofold public health benefit which has primarily driven research interest.
The following is a summary of health benefits associated with purple potatoes.
- Hormonal balance which helps prevent depression.
- Management of high blood pressure
- Immune enhancement
- Positive effect on teeth and bones
- Lowering of plasma IL-6 associated with inflammation
- Promotes heart-healthy decrease in C-reactive protein
- Management of arterial stiffness
Studies Supporting Purple Potato Health benefits
The following scientific studies have produced results supporting the health benefits of purple potatoes.
 | Anthocyanidins and anthocyanins potential health benefits – this study published in 2017 in the Journal of Food and Nutrition reviews the role of anthocyanidins and their nutraceutical properties for health. |
 | Antioxidant Rich Potato Improves Arterial Stiffness in Healthy Adults – the findings of this 2018 study published in Plant Foods for Human Nutrition journal indicate possible benefits on arterial stiffness derived from eating Purple Majesty potatoes. |
 | Comparison of the postprandial (post meal) effects of purple and yellow potatoes – the results of this study published in 2015 in the International Journal of Food Science and Nutrition show that purple potatoes have a positive impact on insulin after taking a purple potato meal. |
 | Effects of anthocyanins on the prevention and treatment of cancer – this 2017 study published in the British Journal of Pharmacology reviews progress on the anticancer activities of anthocyanins and the underlying molecular mechanisms. |
| Health benefits of anthocyanins – this study published in 2015 in International Journal Food Science and Nutrition takes a look at the general health benefits of anthocyanins as found in purple potatoes. |
 | Antioxidants in Potatoes – this study published in 2021 in the journal Molecules takes a review of knowledge available on the current and future potential of potatoes in health and food production. |
What to do with Purple Potatoes
The primary application of purple potatoes is culinary. In a similar fashion as the other different types of potatoes, purple potatoes are an important source of food. In general terms, purple potatoes perform similar gourmet uses as Russet potatoes. The following are some purple potato uses.
- Baking
- Roasting
- Microwaving
- Steaming
- Mashing
- Potato chips
- Sautéed
A study published in Food and Nutrition Sciences (2013) evaluated overall acceptance by consumers of the aroma, appearance and flavor of purple potatoes. The investigation concluded that there were no significant differences in acceptance observed among consumers between purple potatoes and other regular potato cultivars.
This reaffirms the fact that specialty potatoes such as purple potatoes have similar applications as regular potatoes.
Purple Potato Recipes
- Roasted Purple Potatoes – this recipe uses purple potatoes, garlic, olive oil and fresh rosemary springs among other ingredients. The potatoes are boiled first, then drained before being roasted at 400ºF/200ºC.
- Mashed Purple Potatoes – this simple recipe is prepared in much the same way as regular mashed potatoes. The difference is that purple potatoes are used. The potatoes are first boiled for about 17 minutes or until they are tender.
- Peruvian Purple Potato Salad – this recipe uses 2 pounds of purple potatoes which are cooked, peeled, cooled and chopped into small cubes. Other ingredients include shallots, peppers and green apples.
Smashed Purple Potatoes Recipe (Video)
This video demonstrates how to make smashed purple blue potatoes. The potatoes are not mashed but boiled first and then smashed using a fork.
How to Grow Purple Potatoes
Purple potatoes generally follow long established general methods of potato production as applicable to Solanum tuberosum. They are grown from seed tubers and not true seed. However, each purple potato variety grown may call for a certain cultivation approach in order to produce certain results. The grower may thus need to be familiar with the respective requirements.
For example, Adirondack Blue is planted as a seed piece of 71g to 85 g or 2.5 oz to 3 oz at a depth of 7.6 cm to 10 cm or 3 to 4 inches deep. In addition, the recommended spacing when planting Adirondack Blue is 100 cm or 40 inches between rows and 20 cm or 8 inches between plants. This purple potato is ready for harvest in 87 days and is recommended for vine killing prior to harvest for best results.
Home Grown Purple Potato (Video)
This video demonstrates a simple method of growing purple potatoes in the home garden. This method can be used across cultivars with decent results. Furthermore, the method shown here makes growing purple potatoes accessible even to inexperienced home growers.
See our full feature on When to Harvest Potatoes
Conclusion
Purple potatoes are specialty colured-flesh potatoes. They are enjoying growing popularity in North America primarily due to their health benefits linked to high levels of anthocyanins. There are over a dozen purple potato varieties which include non-GMO hybrids released in recent years. In addition, there are also purple heirlooms that have been in existence for hundreds of years. Purple potatoes have a variety of culinary applications which include baking, mashing, roasting and chipping. Although they have a dark pigmentation different from regular potatoes, this has no significant influence on their taste and flavor. Purple potatoes are accessible to the general population due to their ease of growing in the home garden.
