I did not want to focus on the most common Fruits, however. In this post I wanted to present a list of  unique or uncommon Cold hardy fruit trees which can be grown from Gardening Zones 3-7: 

"Jujube grows throughout most of the southern half of North America. For best crops, the tree needs a long growing season and hot and dry weather during ripening. About the only parts of the United States where jujube can't grow are in the North (USDA Zones 5 and colder) and the Gulf Coast where summer rain and humidity prevent optimum fruiting...average winter minimum temperatures between -5° F (zone 6) and -15° F (zone 5) are the likely hardiness limits, trees have survived -25° F" (NGA.) From what I have seen, the Jujube fruit looks like a small apple, then once it has dried on the tree, it simulates a Date fruit.  They are absolutely sweet and crunchy. 

 Ice Cream Banana
Musa acuminata × balbisiana 'Blue Java'

Paw-Paw Tree
Asimina triloba

Hardy Chicago Fig  

Ficus carica 

 Also known as 'Bensonhurst Purple' whose origins are from Sicily, this tree can take sub-freezing temperatures, die back to the ground in the winter, and then re-sprout in the spring and bear Fall fruit on new growth. It is quite suitable for growing in a pot or a greenhouse. "The secret to winter survival is to keep it reasonably dry and above 10°F for the stem or -25°F for the roots. Of course, a fig grown in this manner will take on a shrub-like form rather than a standard tree-form. If a tree shape is desired it would be best to pot it up and sink the container into the ground, then dig it up in late Fall and store it in a garage; 40°F would be ideal, but above 25°F is sufficient  Alternatively, the tree could be taken inside and treated as a house plant" (ManchesterGardenClub).

The Che is related to the Mulberry, but the Che fruit looks identical to the Lychee fruit, resembling a brain. The Che is Native to many parts of eastern Asia from the Shantung and Kiangson Provinces of China to the Nepalese sub-Himalayas. It became naturalized in Japan many years ago, and later was introduced into England and other parts of Europe around 1872, and in 1930 was introduced to the U.S.

"The Che requires minimal care and has a tolerance of drought and poor soils similar to that of the related mulberry. It can be grown in most parts of California and other parts of the country, withstanding temperatures of -20° F...They perform best in a warm, well-drained soil, ideally a deep loam" (California Rare Fruit Growers).  

Gooseberry
Ribes uva-crispa

"Indigenous to many parts of Europe and western Asia, growing naturally in alpine thickets and rocky woods in the lower country, from France eastward, well into the Himalayas and peninsular India" (Gooseberry). Gooseberries grow best in summer humid, cool regions with great winter chilling. Gooseberries are deciduous shrubs, fast growing, and reaches 3 feet tall and 6 feet wide. Gooseberries look like veiny Grapes, usually red or green in color.

Cydonia oblonga

"The fruit is much more common through South America, Europe and the Middle East than it is in North America. You can grow quince between zones 4 and 9, as they can tolerate freezing temperatures during the winters as long as the flowers aren’t hit with a late hard frost. Quince fruit is very tart and sour even when mature..." (Backyard Gardening). Since quince have naturally shallow roots, they may survive in large containers, and may also grow like a bush rather than a tree. They take three years to begin producing fruit.

Native to the Far East, this shrub reaches 4 to 6 foot tall. Self-fertile, not bothered by pests or diseases, tolerates a wide range of soils, and fixes nitrogen in the soil. Goumi plants have silvery leaves underside. They begin producing fruit in two to three years, with fragrant creamy-white flowers in May followed by tasty and aromatic red fruits. Looks like a Goji Berry fruit, but with hints of cherries, apples and black currant flavor. Grows well in USDA gardening Zones 4-9.

Currants

Ribes

"Red, pink and white currants belong to three European species (Ribes rubrum, R. petraeum, R. sativum). Black currants are related to European (R. nigrum) and Asian (R. ussuriense) species.

Other Related Species are the Gooseberry (Ribes grossularia, R. hirtellum), Buffalo Currant (R. aureum), Jostaberry (R. nigrum X hirtellum). Currants grow best in summer humid, cool regions with great winter chilling. They are best adapted to USDA Hardiness Zones 3 through 5...Bushes grown from seed bear when two or three years old" (CRFG). 

Cranberry

Cranberries are low, creeping shrubs or vines up to 7 ft long and 2 to 8 in in height. They "have slender, wiry stems that are not thickly woody and have small evergreen leaves. The flowers are dark pink, with very distinct reflexed petals, leaving the style and stamens fully exposed and pointing forward. They are pollinated by bees" (Cranberry). The berry is initially white, turning into a deep red when fully ripe. Has an acidic taste that can overwhelm its sweetness. Cranberries require an adequate fresh water supply, and a growing season that extends from April to November. They "grow on low-lying vines in beds layered with sand, peat, gravel and clay. These beds are commonly known as bogs or marshes and were originally created by glacial deposits...Cranberries are grown through the northern part of the United States. The major production areas are New Jersey, Massachusetts, Oregon, Washington, Wisconsin and the Canadian provinces of British Columbia and Quebec. Other regions grow cranberries as well, to varying extent, and these include Delaware, Maine, Michigan" (CCCGA).

Elderberry

The American elderberry is a common plant that takes little effort to forage. It is not a rare plant, in fact I consider this plant to be a weed, considering I have identified them on the sides of roads, in the woods, and in yards. Elderberries grow all over North America, so you will not have problems finding/growing this plant. Elderberries fruit best when you plant at least two different varieties. They start producing the first year of transplant but will take 2 to 3 years to produce fruit from seed. When I have harvested elderberries, I found them to be sour in taste; but if that is your thing, there are several varieties of the American elderberry that are good fruit producers, like the Adams, Black beauty, Black Lace, Johns, Nova, Variegated, and York (NGA). Some would say the Poke plant bears fruit similar to the Elderberry, as well as the plant Devil's Walking Stick.

Mulberry

Morus

"Morus alba, white mulberry, and M. nigra, black mulberry, are native to China. Morus rubra, red mulberry, is a North American species, ranging from the mid-Atlantic to Florida and west to Nebraska and Texas. Morus nigra is cultivated throughout Europe for its large, sweet-tart fruit. Morus alba is the hardiest, surviving –25F. and colder, though its fruit quality varies greatly.
The genus name Morus is derived from the Latin ‘mora,’ which means ‘delay,’ and refers to the late leafing habit of the mulberry...This delay ensures that its fruit buds appear well after danger of frost has passed...Mulberries are 30- to 50-foot, fast growing, long-lived deciduous trees with alternate, simple, lobed to undivided leaves. Leaves on one tree can be lobed and [un-lobed]. Though both monoecious (male and female flowers on one plant) and dioecious (male and female flowers on separate plants), many trees are self-pollinating. Trees are also known to change sex. The tree flowers inconspicuously in late spring on the current season’s wood and on spurs of old wood...Fruits, which ripen in midsummer, are small fleshy drupes, resembling a tightly beaded blackberry. Fruit color ranges from white to lavender to red and purplish-black. Some mulberries are seeded, though I have known over two dozen trees and never met a seed. The flavor is mild and very sweet, but M. alba is said to lack the perfect blend of sweetness and tartness of M. nigra. I have tasted only M. alba and love it. If I need the tartness for any reason, I mix in some under-ripe fruits. As I noted before, beware: The dark fruit stains badly" (MOFGA). 

Chokeberry 

Aronia melanocarpa

This shrub can be planted in Zones 3-8., and usually grows to 3-6' tall and wide, though it can be up to 10' in width.You can plant the black chokeberry in either full sun or partial shade...Black chokeberry has dark green leaves that are 1-3" long and lanceolate or elliptical in shape. In the fall they change to reddish hues, similar looking to the Blueberry bush. "The white flowers appear during springtime and come in clusters called corymbs. The fruit produced is a small black pome that has tannins which pack pucker power" (Myers).

Ribes × nidigrolaria

"Jostaberries are hybrids of black currant and the American gooseberry, R. hirtellum, produced in Germany, 1930s-50s... The bush is very tall, thorn-less, tends not to branch and requires the space of 2 currant bushes. The foliage is glossy, larger than gooseberry, lobed, scentless and resists mildew. It survives full sunlight but requires much winter chilling. The lateral buds usually shed, leaving blind branches. Purple or brownish-red fruit are borne on lax, few-berried strigs. They are the size of small gooseberry and lacking in flavor, suitable only for experimentation. Buffalo currant produces comparable fruit more abundantly in less space and is recommended instead" (CRFG).

Saskatoon (Serviceberry)

Amelanchier alnifolia

"Native to North America from Alaska across most of western Canada and in the western and north-central United States. Historically, it was also called "pigeon berry". It grows from sea level in the north of the range, up to 2,600 m (8,530 ft) elevation in California and 3,400 m (11,200 ft) in the Rocky Mountains...Saskatoons are adaptable to most soil types with exception of poorly drained or heavy clay soils lacking organic matter. Shallow soils should be avoided, especially if the water table is high or erratic. Winter hardiness is exceptional, but frost can damage blooms as late as May. Large amounts of sunshine are needed for fruit ripening. With a sweet, nutty taste, the fruits have long been eaten by Canada's aboriginal people, fresh or dried" (Amelanchier alnifolia).

                                 Hippophae rhamnoides

 "The plant is a thorny shrub that can survive the harshest weather conditions.  As it turns out the Prairies are an ideal habitat for Sea Buckthorn...Sea Buckthorn has an extensive rooting system and a nitrogen fixation property. Seabuckthorn has been planted to rejuvenate marginal land and soil conservation" (Solberry Seabuckthorn). Sea Buckthorn is an "incredibly important natural resources in the mountainous regions of China and Russia, and the Canadian prairies. The plant will grow naturally in both sandy, and clay soils. In fact the plant will thrive in nearly any soil type, but it is extremely intolerant of shady planting sites. The shrubs themselves are also very cold-hardy. The plants can withstand winter temperatures of up to -40 degrees Celsius (-43 degress F). It is also commonly found growing at high altitudes of 4000 to 14000 feet" (Sea buckthorn insider).

Punica granatum

The Medlar
Mespilus germanica

"Indigenous to southwest Asia and also southeastern Europe, especially the Black Sea coasts of Bulgaria and of modern Turkey. It may have been cultivated for as long as 3000 years...Requires warm summers and mild winters and prefers sunny, dry locations and slightly acidic soil. Under ideal circumstances, the deciduous plant grows up to 8 metres (26 ft) tall" (Mespilus germanica). Generally has a lifespan of 30-50 years, and is shorter and more shrub-like than tree-like. 

Hawthorn berry

Crataegus

"Native to temperate regions of the Northern Hemisphere in Europe, Asia and North America. The name "hawthorn" was originally applied to the species native to northern Europe, especially the common hawthorn C. monogyna, and the unmodified name is often so used in Britain and Ireland. The name is now also applied to the entire genus and to the related Asian genus Rhaphiolepis...the Common Hawthorn, C. monogyna, are edible but the [flavor] has been compared to over-ripe apples...the fruits of the species Crataegus pinnatifida (Chinese hawthorn) are tart, bright red, and resemble small crabapple fruits." (Crataegus).

Silver buffaloberry

 Shepherdia argentea

This thorny, deciduous shrub grows up to 20 feet tall. It is native to northern and western North America. The plant grows in USDA Zone 2, so it tolerates cold winters, drought and also tolerates infertile soil. 

Thimbleberry 

 Rubus parviflorus

 "Native to western and northern North America, and the Great Lakes region...Thimbleberry fruits are larger, flatter, and softer than raspberries" (Rubus parviflorus). The plant reaches up to 10 feet tall and blooms white petals. The leads grow to 10 inches long, fuzzy, deciduous maple-like shape. The plant needs Full sun to shade with moist to dry, humus rich soil. "Thimbleberries do not grow well on sandy or gravelly soils, but in the Northwest, a small percentage grow in wet soils" (Rainy side Gardeners).

This list of Fruit bushes and trees are a fraction of what is possible to grow in cold climates. As plant species continue to cross-pollinate, there will be that much more fruit to grow. Of course there are many more varieties of Berries and Currants that grow in cold climates, For example, Sourberry (Rhus trilobata), Wax Currant (ribes cereum), American silverberry (elaeagnus commutata), Creeping barberry (mahonia repen), boysenberry, huckleberry, dewberry, tayberry, youngberry, and Marionberry. 

Do not limit yourself to fruit bushes and common cold hardy fruits. From GardenWeb.com, one gardener said he was growing a Papaya tree in Zone 5/6a, which he grows in a container outside during the Summer, and he brings the Papaya tree inside during the Winter next to a South facing window. I was very shocked that he even posted pictures of his Papaya harvest. Click the link for details and pictures of the Papaya growing in a cold climate: Fruiting Papaya in Zone 5/6.

Northern gardeners grow sub tropical fruits like Limes, Lemons, Mandarin oranges, as well as tropical pineapple and Mangoes in containers. When growing Fruit plants in containers, you will be able to relocate the fruit inside your home or in a greenhouse where it will be protected over winter. I have a post on Growing Fruit in Containers: Grow Veggies & Fruit trees in Containers (Limited Space & Urban gardening.