When N.E. Hansen came to America as a young man, he ended up in the bleak climate of South Dakota. Undeterred, he responded by scouring the world for hardy plants to enrich the lives of the farmers around him. His best-known legacy is a purple-leafed shrub that is a staple for every gardener facing the trials of icy winters.

Gardeners in cold parts of the country, and up in Canada, are very familiar with the Purple-leaf Sand Cherry, Prunus x cistena. In those areas this plant even suffers from over-abundance, and its purple-red leaves can be found in almost every garden. Six to eight feet tall at most, it has small, single pink flowers in spring, before the new leaves appear. Those who come from warmer areas will certainly notice its ubiquitous presence in zones 2, 3 and 4 – but in colder areas you go with what will grow. Despite its many faults – it is short-lived, disease prone, and it does not begin to rival the beauty of flowering cherries – this plant is a valuable shrub for gardeners in cold zones.

Whenever you see that ‘x’ in a plant name, it is almost certain that someone, somewhere, was behind its creation. In Gerd Krüssman’s magnum opus, the 3-volume ‘Manual of Cultivated Broad-leaf Trees & Shrubs’, we find this brief sentence, “Developed by N.E. Hansen in the USA around 1910.” But who was N.E. Hansen?

Niels Ebbesen Hansen arrived in New York on August 21, 1873. His father had come to America from their home in Denmark a year before, and now some of his family had come to join him. Niels was only seven years old, and before he was ten his artist father moved the family to Des Moines, Iowa, finding work decorating the interior of the State Capitol, and later inside the homes of the wealthy. It was an uncertain income, but the family survived. Niels left school at fifteen, to earn money, but his ambitions for a college education drove him on, and he completed High School by studying on his own. An inheritance from an aunt back in Denmark made it possible for his to go to Iowa Agricultural College. It was there that he encountered Professor Joseph L. Budd.

There is a long tradition in America of seeking improvements in the plants that can be grown, going back at least to Thomas Jefferson, who returned from his incognito trip to France and Italy in 1790 not just with a French chef, pasta and macaroons, but also with seeds of Italian rice that grew in fields, not flooded paddies. Professor Budd was strongly in that tradition, and he imported Russian plants to test their toughness for life on the Great Plains. After Hansen graduated he worked in nurseries for a few years, before Budd brought him back as a graduate student, creating an assistantship to make it possible. Hansen’s senior-year thesis had been on fruit breeding, and so was the work for his Master’s.

In 1894 Hansen travelled to Europe, encouraged by Budd, and financed by an advance on his salary. He returned even more convinced that the way to create hardier plant varieties was by crossing existing less-hardy plants with tough American relatives, and then hoping to find among the offspring plants that were tough, but as excellent in quality as their more delicate parent.

There was another professor at Iowa, the Scottish-American James Wilson. Leaving his academic career behind, Wilson moved into politics, and by 1897 he was the Secretary of Agriculture in Washington. By that time Hansen had graduated and was a professor at South Dakota Agricultural College, a much colder area than Iowa. He saw that the need for cold-hardy and drought-resistant plants was even more pressing. One of Wilson’s first actions was to send Hansen to Russia to bring back hardy plants. He returned with ‘Cossack’ Alfalfa, which with his other collections made a major contribution to modern hardy varieties. The seed was given to him by V.R. Williams from the Imperial Agricultural College of in Moscow. He also came back with ‘Dolgo’, a red crab-apple still widely grown today, and a plant he would use extensively in his own breeding.

Malus baccata 'Dolgo'

While in Russia Hansen travelled through Siberia, eventually arriving in Vierney, present day Almaty, the capital city Kazakhstan at the time. There he saw something remarkable. A civil servant and amateur botanist called Vladislav E. Niedzwiecki showed him an apple with striking red-flesh under a green skin, but also with red flowers, leaves, and red inner bark. This was Malus niedzwetzkyana, (named after its finder, and now on the IUCN Red List as endangered) which grows wild in the Tien Shan mountains. Hansen seems to have become obsessed with this fruit. At considerable risk and hardship, he followed it through bazaars and markets, even crossing the Chinese border in an attempt to trace it to its source.

Back home, with precious scion wood, Hansen saw the opportunity to create not one, but two new classes of apples. First, a hardy cooking and eating apple, by crossing this new crab with hardy apples, and secondly a red-flowering crab apple for the gardens of hard-working farmers on the Plains. He certainly succeeded in his second goal, producing his ‘Rosy Bloom’ series of crabs, with purple-red blossoms, of which ‘Hopa’ is most widely grown today.

To his surprise, though, he found himself beaten out in his primary goal, although he did produce some red-fleshed apples, most notably ‘Almata’, still available today, although not highly-regarded. His nemesis turned out to be an eccentric Californian, the self-taught fruit breeder Albert F. Etter, who had 600 varieties at his disposal at his isolated homestead in the King’s Range mountains of north-western California. Among them was ‘Surprise’, an old German red-fleshed apple brought over in the 1840s to the Ohio River Valley. Despite its different origin, this was most probably a form of Malus niedzwetzkyana – which Hansen thought was his alone. In the much more hospitable climate of California it didn’t take Etter long to produce a range of trees with red-fleshed fruit. Of his thirty-odd seedlings, one would much later be patented as ‘Pink Surprise’, and it is still available, even sometimes appearing in supermarkets as an upscale novelty item. When Hansen heard of Etter’s trees, he surrendered, writing to him, “Mr. Etter, you have defeated me in my destiny.” Compared to the children of ‘Surprise’, Hansen’s sour red-fleshed apples, although of better color, were a flavor dud.

Hansen then turned his attention to plums and cherries, another useful farm crop, for baking and preserves, but not hardy enough for the northern plains. Following his established approach of crossing European varieties with hardy American plants, he picked the western sand cherry for his native plant. This is an especially tough form of Prunus pumila, a plant that is found across northern North America. The Western form, Prunus pumila var. besseyi, had been named by Liberty Hyde Bailey after Charles Bessey, another of Hansen’s professors. Bessey had spoken of this plant – hardy to zone 2, drought-resistant, and bearing good crops of cherry-sized fruit – in glowing terms to the American Pomological Society in 1889. “No native fruit appears more promising,” he told them. In 1892 Hansen, Bessey’s assistant at that time, planted several thousand seedlings, and then selected those with the largest and best fruit. It took 14 generations before he released the ultimate ‘Hansen bush-cherry’ in 1941, a form with large fruit and small pits, that is still available, and even enjoying a mild revival for edible landscaping.

He also fertilized his sand cherries with the pollen of several Prunus species. His greatest success was with Luther Burbank’s Japanese plum and he created two new plum varieties, ‘Opata’ and ‘Sapa’. These very hardy, early-fruiting small plums are still available.

Another plant he used as a pollen-source was the myrolaban, or cherry plum, Prunus cerasifera. This large tree, hardy to zone 5b, and reaching 30 or 40 feet, produces small red fruits, but is more admired today for its bold display of single white blossoms, one of the earliest blooming of the Prunus. There are also several forms with purple leaves, pink flowers and dark-purple fruits, most notably the variety Atropurpurea’ (called purple-leaf Persian plum by Hansen). It is reasonable to assume that Hansen, with his love of richly-colored fruits, chose this variant as a parent for its fruit color, and perhaps not so much for foliage. After all, his primary goal was edible fruits. He must have had some problems obtaining pollen, since he reports in 1901 that his outdoor plants in South Dakota were winter-killed. He may have grown plants in pots and stored them, as he did for peaches.

Prunus x cistena

The resulting seedlings were very hardy, but they must have been a disappointment to him – they fruited only a little, and the fruit was small and of no value. Nonetheless, the plant had charm. Besides its pink flowers and persistent purple foliage, it’s small size made it ideal as an ornamental garden plant. The purple-leaf sand cherry was born. Hansen named it ‘Cistena’, from the Sioux word cistiåna, meaning ‘small’. Another seedling, ‘Stanapa’, which was larger, seems to have been lost from cultivation. In a 1926 publication Hansen wrote of these plants, “Fruits of no value and sparingly produced. But as ornamental shrubs with red leaves the varieties Cistena and Stanapa are popular in western gardens.”

Prunus x cistena foliage

Hansen’s plants were mainly propagated and distributed by the pioneer nurseryman Charles W. Gurney, founder of Gurney’s Seed and Nursery Company. Hansen had a long and close relationship with him, and with his son Deloss Butler Gurney. Later Hansen’s own son, Carl Andreas, would establish the Hansen Nursery. It would have been these growers who were responsible for the distribution of the purple-leaf sand cherry, as well as another ubiquitous cold-climate plant that Hansen brought to America, the Siberian pea-shrub, Caragana arborescens.

Hansen was to return to Russia two more times, but then Wilson retired, and without his protection he fell out of favor with the Department of Agriculture. He was accused of overspending, and of bringing back seed from Russian institutions, hardly collecting in the wild at all. He made an enemy of Frank Meyer, famous for his Chinese collections, and Hansen was effectively grounded. His explorations seemed at an end, but then his friends in South Dakota had the state government fund his work, much to the annoyance of Meyer. He returned to Russia, but back home he was now a controversial figure, accused of being a horticulturist meddling in agronomy, and single-minded in promoting his Russian alfalfa. Turbulent years followed, dogged by disputes and financial difficulties from his failed nursery business, but he kept exploring, travelling to China in 1924, and to Soviet Russia in 1934.

As time passed the disputes faded, and honors flowed in. Hansen accumulated medals and awards, his breeding activities continued, and he became a horticultural celebrity in South Dakota and beyond. The State University erected a memorial statue of him in 1949.

Niels Hansen died in 1950, at the age of 84. Of all his work, the ornamental purple-leaf sand cherry is the most well-known. His vision of prairie farmers living self-sufficiently on his hardy fruits never arrived, destroyed by long-distance haulage, refrigeration and the supermarket.

Lead photograph of N.E. Hansen from the collection of the South Dakota Agricultural Heritage Museum, South Dakota State University. Brookings, SD