Difficulty
  jujubes require minimal effort to manage.
∙ wet or dry climate
Bloom
  jujubes awaken from dormancy late enough to generally avoid frost damage.
Ripens
  4+ months? (hot climate), aim for the earliest in cool climates (experimental)
Chill Hours
  200 or less
Pollination
  self-fertile, self-sterile
pH
  5.6 to 6.5 (preferred), 5.1 to 7.8 (acceptable), 4.5 to 8.4 (tolerable)
Yield
  1 - 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 the humid subtropical (Cfa) climate 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 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.  Furthermore, if the grow season is long enough, some varieties may produce two crops, but 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 as to how long this lasts.  In New Mexico, jujube flowers were between 5mm to 7mm in diameter, depending on the variety,[2] and each variety produced a fairly consistent number of flowers at each node, depending on the section of the branch.  Those near the beginning and end generally had less flowers.[2]

Jujubes can either be a morning blooming-type (AM) or an afternoon blooming-type (PM).[2] While the former opens their flowers in the morning, the pollen is primarily released in the afternoon, and it continues (along with nectar production) until the end of the day.  The afternoon blooming-type releases pollen in the late afternoon as well as the next morning.  However, rain or cloudy weather can delay this process for a few hours.[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" that is seen with the information provided for some varieties 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 'So', and '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 diseases that affect jujubes in the United States.  In Asia, jujube witch's broom is considered to be the most destructive, often killing the tree 3 to 5 years after infection, but a number of resistant varieties have been identified and are being used in breeding programs.[3] Alternatively, trunk injections of various antibiotic combinations have been used to cure infected 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 appear to be highly resistant to fruit shrink disease.[5]


Additional Notes



Jujube trees are generally thorny, but they become less so 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, .




Read More

Jujube: Ziziphus jujuba

varieties in this section generally share these traits (unless stated otherwise)
There are no significant pests or diseases that affect jujubes in the United States, but they do have a minor issue that is related to their environment.  They are known for being fairly precocious, but production can be delayed in wet climates.  This is particularly true for varieties that produce large fruit.  While they are exceedingly drought resistant, supplemental irrigation during bloom, as well as exposure to sunlight throughout the day, may help improve this seemingly temporary problem. 

Jujubes require minimal effort to manage.  Furthermore, they wake up from dormancy late in the season, which helps them avoid frost damage.  They do require a long grow season, though.  The earliest ripening varieties should be prioritized in their more northern range.  One site claims they can handle temperatures as low as -28F. It does appear that they cannot handle anything lower; however, some varieties may be able to thrive in hardiness zone 4b.

Ant Admire

🔍
Blooms
💮
•    ◦ afternoon blooming
Ripens
🍏
• early-mid?
Growth
• fewer thorns
Fruit
• oval/elongated

Autumn Beauty

🔍
Alias
• Qi Yue Xian
Ripens
🍏
• early
Fruit
• sweet/complex
• round, up to 2"

The young fruit of Autumn Beauty are supposedly burgundy in color, but they turn green around or before they reach 1.5 centimeters in length.

Black Sea

🔍
selected in Yalta, Ukraine
Ripens
🍏
• early-mid?
Fruit
• very sweet
• round/oval
Afflictions
• Black Sea may produce semi-well at a young age in wet climates.

Bok Jo

🔍
originated in Korea
Ripens
🍏
• mid?
Growth
• large leaves
Afflictions
• Bok Jo produces well at a young age in wet climates.

While the sample size is small, Bok Jo appears to be one of the most consistent producers in wet climates.

Chico

🔍
Developed in California
Blooms
💮
•    ◦ morning blooming
Ripens
🍏
• mid
Fruit
• sweet-tart
• medium, apple-shaped

Coco

🔍
selected in Yalta, Ukraine
Ripens
🍏
• early-mid
Afflictions
• Coco may produce semi-well at a young age in 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.  It could use more experimentation.

Contorted So

🔍
Originated in China.  Imported to the US in 1914.
Blooms
💮
•    ◦ morning blooming
• ~ 6mm in diameter
• ~ 0-2 per node (early section), 3-4 per node (mid section)
Ripens
🍏
• early? (early-mid)
Growth
• contorted branches
Fruit
• round/oval, up to 1.25"
Afflictions
• So may produce semi-well at a young age in wet climates.

There may be more than one selection under the name of 'So' circulating the US.

GA 866

🔍
developed in Chico, California?
Blooms
💮
•    ◦ afternoon blooming
• GA 866 may produce fewer flowers than most varieties.
Ripens
🍏
• mid-late?
Fruit
• very sweet
• elongated/oval, 1" x 2"

GA866 is known for being a very shy producer.  It has been reported that one tree took 8 years and another 10 years to start producing fairly well. 

GA866 produces very sweet fruit, up to 45 brix has been measured (low 20's to low 30's is fairly common).  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?
Fruit
• cardboard
• large, probably around 2" in diameter
• Globe is most circular jujube I have seen.

Honey Jar

🔍
Blooms
💮
•    ◦ afternoon blooming
Ripens
🍏
• early?     ◦ precocious
• may ripen later near the west coast
Fruit
• very sweet, crisp, juicy
• 1", round, rounded-square, or honeyjar-shaped
Afflictions
• 'Honeyjar may produce semi-well at a young age in wet climates.

Honeyjar first becomes edible when the fruit turn yellow.

Lang

🔍
Originated in China.  Imported to the US in 1908.
Blooms
💮
•    ◦ morning blooming
• ~ 7mm in diameter
• ~ 1-2 per node (early section), 3-4 per node (mid section)
Ripens
🍏
• early-mid
Growth
• fewer thorns
Fruit
• pear-shaped, 1.5"
Afflictions
• Lang may produce semi-well at a young age in wet climates.

Lang has a fairly poor reputation when it comes to fresh eating, and there are better varieties for drying as well.

Li

🔍
Originated in China.  Imported to the US in 1914.
Blooms
💮
•    ◦ afternoon blooming
• ~ 6.1mm in diameter
• ~ 1 per node (early section), 1-3 per node (mid section)
Ripens
🍏
• mid
Growth
• fewer thorns
Fruit
• sweet to sweet-tart
• large, round/apple-shape
Afflictions
• Li may produce semi-well at a young age in wet climates.

Li is quite variable in flavor, possibly more so than the average variety.  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).

Massandra

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

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
• round, 2"
Afflictions
• Shanxi Li may produce semi-well at a young age in wet climates, but this may be limited to areas that are quite hot as well.

Sherwood

🔍
Discovered in Louisiana
Blooms
💮
•    ◦ afternoon blooming
• ~ 6mm in diameter
• ~ 1-3 per node (early section), 6-8 per node (mid section)
• Sherwood may produce fewer flowers than most varieties.
Ripens
🍏
• mid-late
Growth
• fewer thorns, large leaves
Fruit
• sweet
• 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 wet and dry climates.  Sherwood is well liked in the western half of the US. I have only seen one report from the east, and it was poor.

Sihong

🔍
Blooms
💮
•    ◦ afternoon blooming
• ~ 6.5mm in diameter
• ~ 0-3 per node (early section), 6-9 per node (mid section)
Ripens
🍏
• mid     ◦ precocious
Fruit
• sweet and complex
• round/apple/elongated/oval, roughly 1.5" x 1.5"

Sihong is considered to be one of the best for drying.

Sugar Cane

🔍
Blooms
💮
•    ◦ morning blooming
• ~ 6.5mm in diameter
• ~ 0-2 per node (early section), 5-7 per node (mid section)
• self-sterile?
Ripens
🍏
• early
Fruit
• very sweet
• oval, 1.2" x 1.4"

Tae Seoul Jo

🔍
originated in Korea
Ripens
🍏
• early-mid? (mid)
Fruit
• very sweet, juicy
Afflictions
• There is some evidence that Tae Seoul Jo can produce quite well at a fairly young age in wet climates.

Tigertooth

🔍
Ripens
🍏
• late?
Growth
• fewer thorns
Fruit
• 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.

Winter Delight

🔍
Alias
• Mango Dong Zho
Ripens
🍏
• late
Fruit
• 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 (hence its name).

Xu Zhou

🔍
originated in China
Ripens
🍏
• late
Fruit
• oval/elongated
Afflictions
• Xu Zhou may produce at least semi-well at a young age in wet climates.