Zone
  5/6a (4)
Pollination
  self-fertile, self-sterile
Blooms
  late? (very late)
(in comparison to other species)
Ripens
  4+ months? (hot climate), aim for the earliest in cool climates (experimental)
(from the start of the grow season)
Chill Hours
  200 or less
pH
  5.6 to 6.5 (preferred), 5.1 to 7.8 (acceptable), 4.5 to 8.4 (tolerable)
Yield
  0 - 4 years
Tolerant
  poor soil, saline soil

Native Range and Climate



The native range of Ziziphus jujuba is unknown due to extensive cultivation throughout Eurasia, but it is believed to be somewhere between the eastern tip of the mediterranean basin and China.

Jujubes are extremely drought and heat tolerant once established, but irrigation during bloom appears to help improve their often poor fruit set.  This has been observed in not just hot and dry climates, but in humid subtropical climates as well.  However, older trees, as well as varieties that produce smaller fruit, may not require as much or any supplemental irrigation, since both factors seem to help prevent fruit drop.  Additionally, gibberellic acid (ga3) or a borax solution, sprayed during bloom, may also help increase fruit set.[1]

In regions between the two environmental extremes, jujubes may perform very well without supplemental irrigation.  In very hot climates, irrigation can also prevent the fruit from drying out before they fully develop.  In wet climates, exposure to sunlight throughout the day is very important for fruit set as well.

If the grow season is long enough, some varieties may produce two crops.  In hot desert climates, the first crop may be of poor quality due to extreme heat.


Flowers and Blooming-type



Jujubes bloom for a very long time, 6 weeks or more, on current year's growth, but each flower only produces pollen and nectar for a day or less, depending on their blooming-type.[2] The stigma becomes receptive a few hours after pollen and nectar start to produce,[2] but it is unclear how long they remain receptive.  In New Mexico, jujube flowers were between 5mm to 7mm in diameter, depending on the variety.[2] Each variety also produced a fairly consistent number of flowers at each node, with bunches often consisting of more flowers on the middle section of the branch.[2]

Jujube varieties can either be a morning blooming-type (AM) or an afternoon blooming-type (PM), indicating that their flowers will open during a few hour period within the morning or the afternoon.[2] However, rain or cloudy weather can delay this process for a few hours.  Morning blooming varieties only produce pollen and nectar until the end of the day, while afternoon blooming-types will produce for a few hours later in the day and begin to produce again the next morning.[2]

NOTE: Jujube varietal traits, such as the shape and size of the fruit, may vary – to some extent – based on the year, location, and, perhaps, the age of the tree.  Information on flower size and their average number per node is based entirely on data from New Mexico at this time.  The "early section" is based on the first two nodes of each flowering branch.


Mislabeling



In the US, some varieties have a reputation for regularly being mislabeled.  For example, there may be more than one contorted variety labeled as 'So', and the variety 'Autumn Beauty' (an early ripening variety) was once, and may still be, regularly sold under the name 'Winter Delight' (a late ripening variety) by at least one or two major nurseries.  Silverhill and Tigertooth are often considered to be the same variety, but they may have slight differences.


Pests and Disease



There are no significant pests or disease that affect jujubes in the United States.  In Asia, jujube witch's broom is considered to be the most destructive disease, often killing the tree in 3 to 5 years after infection, but a number of resistant varieties have been identified and used in breeding programs.[3] Trunk injections of various antibiotic combinations have also been used to cure infected jujube trees with a high rate of success.[3] Other diseases that can cause significant damage to the crop include leaf-rust[4], fruit shrink disease, and fruit rots, however, many varieties appear to be highly resistant to fruit shrink disease.[5]


Additional Notes



Jujube trees are generally thorny, but they become less thorny as they age.  They are also known to sucker profusely.
1. Effect of Different Cultural Treatments on Yield and Physical Characteristics of Ziziphus Jujuba mill. Grown in Czech Republic.
2.
3. The Resistance of Jujube Trees to Jujube Witches' Broom Disease in China, .
4. Harpin induces rust disease (Phakopsora zizyphi-vulgaris) resistance on winter jujube (Ziziphus jujuba Mill. cv. Dongzao), .
5. Field Resistance to Fruit Shrink Disease in Chinese Jujube Germplasm, .



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Jujube
Ziziphus jujuba

Ant Admire

Blooms
💮:
  .......   :   afternoon blooming
Ripens
🍏:
early-mid?
Fruit Size
:
oval/elongated
fewer thorns

Autumn Beauty

Alias
:
Qi Yue Xian
Zone
:
5
Ripens
🍏:
early

Flavor
:
sweet/complex
Fruit Size
:
round, up to 2"
Young fruit from Autumn Beauty are supposedly burgundy in color, but they turn green around or before they reach 1.5 centimetres in length.

Like other jujube varieties with large fruit, there may be a delay in production in wet climates.  Supplemental irrigation during bloom may help solve this seemingly temporary problem.  Varieties that produce small fruit seem to also suffer from this problem, but to a lesser extent, since they often hang on to a few of them.  Exposure to sunlight throughout the day is also required.

Black Sea

selected in Yalta, Ukraine
Ripens
🍏:
early-mid?
Flavor
:
very sweet
Fruit Size
:
round/oval
Afflictions
:
At least somewhat resistant to wet climates.

Bok Jo

originated in Korea
Ripens
🍏:
mid?
Afflictions
:
Resistant to wet climates.
While the sample size is small, Bok Jo appears to be one of the most consistent producers in wet climates.

Other varieties have produced well in such climates for a small number of people, but they are shy bearers for many others.  In addition to sun exposure throughout the day, supplemental irrigation, particularly during bloom and early fruitset, may be some of the reasons for their success.

Bok Jo produces larger leaves than most jujube varieties.

Chico

Developed in California.
Blooms
💮:
  .......   :   morning blooming
Ripens
🍏:
mid

Flavor
:
sweet-tart
Fruit Size
:
medium, apple-shaped
Either the first Chico's to ripen are not as good as the rest or they are best eaten when they are mostly brown.

Coco

selected in Yalta, Ukraine
Ripens
🍏:
early-mid
Flavor
:
mild coconut?
Afflictions
:
At least somewhat resistant to wet climates.
there is evidence that the "coconut-like" flavor often mentioned by nurseries is somewhat legit, but it's supposedly quite mild.  almost no one talks about this variety, needs more experimentation.

Contorted So

Originated in China. Imported to the US in 1914.
Zone
:
5
Blooms
💮:
  .......   :   morning blooming
~ 6mm in diameter
~ 0-2 per node (early section), 3-4 per node (mid section)
Ripens
🍏:
early? (early-mid)

Fruit Size
:
round/oval, up to 1.25"
Afflictions
:
Somewhat resistant to wet climates.
There may be more than one cultivar named So.

contorted branches

GA 866

developed in Chico, California?
Zone
:
5
Blooms
💮:
  .......   :   afternoon blooming
May produce fewer flowers than most other varieties.
Ripens
🍏:
mid-late?

Flavor
:
very sweet
Fruit Size
:
elongated/oval, 1" x 2"
GA866 is known for being a very shy producer.  It took one tree 8 years and another 10 years to start producing well, and even then, it may end up being less productive than most other varieties.

GA866 produces very sweet fruit, up to 45 brix has been measured (low 20's to low 30's is fairly common for jujubes).  It may be one of the better varieties for drying, but plenty of others seem to be preferred for fresh eating.

Globe

Blooms
💮:
  .......   :   morning blooming
~ 5.8mm in diameter
~ 0-1 per node (early section), 2-3 per node (mid section)
Ripens
🍏:
late?

Flavor
:
cardboard
Fruit Size
:
large, probably around 2" in diameter. most circular jujube I have seen.

Honey Jar

Zone
:
5
Blooms
💮:
  .......   :   afternoon blooming
Ripens
🍏:
early?   :   precocious
may ripen later near the west coast

Flavor
:
very sweet
Texture
:
crisp, juicy

Fruit Size
:
1", round, rounded-square, or honeyjar-shaped
Afflictions
:
Somewhat resistant to wet climates.
Honeyjar becomes edible when the fruit turn yellow.

Lang

Originated in China. Imported to the US in 1908.
Zone
:
5a
Blooms
💮:
  .......   :   morning blooming
~ 7mm in diameter
~ 1-2 per node (early section), 3-4 per node (mid section)
Ripens
🍏:
early-mid

Fruit Size
:
pear-shaped, 1.5"
Afflictions
:
At least somewhat resistant to wet climates.
Lang has a fairly poor reputation when it comes to fresh eating, and there are better cultivars for drying as well. 

fewer thorns

Li

Originated in China. Imported to the US in 1914.
Zone
:
5a
Blooms
💮:
  .......   :   afternoon blooming
~ 6.1mm in diameter
~ 1 per node (early section), 1-3 per node (mid section)
Ripens
🍏:
mid

Flavor
:
sweet to sweet-tart
Fruit Size
:
large, round/apple-shape
Afflictions
:
At least somewhat resistant to wet climates.
Li is quite variable in flavor, possibly more so than the average cultivar.  It ranges from average to excellent, depending on climate/weather and the age of the tree (older is linked to better quality and possibly even earlier ripening).

Li is somewhat resistant to wet climates, and like the others in this category, it will likely require supplemental irrigation during bloom while the tree is fairly young to help prevent complete fruit drop.  Exposure to sunlight throughout the day is also required.

fewer thorns

Massandra

developed in Yalta, Ukraine
Ripens
🍏:
early (early-mid)
Fruit Size
:
sabertooth-shaped, quite small

R4T3

Ripens
🍏:
mid?
Flavor
:
sweet
Fruit Size
:
elongated pepper-shaped, 2.5"

Redlands 4

discovered in Redlands,California
Ripens
🍏:
early-mid? (mid)
Fruit Size
:
large, round/apple-shape
Afflictions
:
At least somewhat resistant to wet climates.

Shanxi Li

Blooms
💮:
  .......   :   afternoon blooming
~ 6.3mm in diameter
~ 0-2 per node (early section), 1-2 per node (mid section)
Ripens
🍏:
mid?   :   precocious

Fruit Size
:
round, 2"
Afflictions
:
At least somewhat resistant to wet climates? (may perform better with hot summers)

Sherwood

Discovered in Louisiana.
Blooms
💮:
  .......   :   afternoon blooming
~ 6mm in diameter
~ 1-3 per node (early section), 6-8 per node (mid section)
May produce fewer flowers than most other varieties.
Ripens
🍏:
mid-late

Flavor
:
sweet
Fruit Size
:
oval/flat-top, 1" x 1.25"
Sherwood tends to take longer than usual to start producing, especially if you are waiting for a heavy crop (7-10 years).  This seems to be a problem in all climates.  Sherwood is well liked in the western half of the US.  I have only seen one report in eastern US, and it was poor.

Sherwood produces larger leaves than most jujube varieties.

fewer thorns

Sihong

Zone
:
5
Blooms
💮:
  .......   :   afternoon blooming
~ 6.5mm in diameter
~ 0-3 per node (early section), 6-9 per node (mid section)
Ripens
🍏:
mid   :   precocious

Flavor
:
sweet and complex
Fruit Size
:
round/apple/elongated/oval, roughly 1.5" x 1.5"
Sihong is considered to be one of the best for drying.

Sugar Cane

Zone
:
5
Blooms
💮:
  .......   :   morning blooming
~ 6.5mm in diameter
~ 0-2 per node (early section), 5-7 per node (mid section)
Ripens
🍏:
early   :   self-sterile?

Flavor
:
very sweet
Fruit Size
:
oval, 1.2" x 1.4"

Tae Seoul Jo

originated in Korea
Zone
:
5
Ripens
🍏:
early-mid? (mid)

Flavor
:
very sweet
Texture
:
juicy
Afflictions
:
Resistant to wet climates?
There is some evidence that Tae Seoul Jo will produce well in wet climates.

Tigertooth

Zone
:
5
Ripens
🍏:
late?
Fruit Size
:
elongated, 1" x 1.5"
Tigertooth and Silverhill are often considered to be the same variety.  They may have some slight differences, but this could have been due to mislabeling.

fewer thorns

Winter Delight

Alias
:
Mango Dong Zho
Zone
:
5
Ripens
🍏:
late
Fruit Size
:
up to 2"
Winter Delight is sometimes labeled as an early ripener, possibly due to a major nursery mislabeling Autumn Beauty as a Winter Delight in the past.  It is, in fact, one of the last to ripen.

Xu Zhou

originated in China
Zone
:
5
Ripens
🍏:
late

Fruit Size
:
oval/elongated
Afflictions
:
Resistant to wet climates? (at least somewhat)