Kishu mikan

In the 2010s, genetic sequencing allowed resolution of taxonomic debate, placing kishus and a number of other mandarin varieties as mutated clones of one another.

[5] The Kishū Tokugawa family, the Kishu branch of the influential Tokugawa clan, ruled Kishū Domain, and is said to have promoted the farming of mandarins on the hillsides around Arida, which were too steep to be readily terraced for rice production.

Kinokuniya Bunzaemon (1669-1734) grew rich transporting the fruit to Edo (modern-day Tokyo).

They thought it was "cute" and went on to be the first to produce kishus commercially in the United States with the planting of an initial block of 50 specially ordered kishu trees in Ojai Valley, California.

[12] The fruit is enveloped in a thin skin (0.11 cm or 0.043 in thick[citation needed]) which secretes a mildly aromatic oil.

[12] The candy-like taste, loose peel, and small size make kishu mandarins popular with children.

[2][14][12] Kishu mandarin trees are commonly planted in household gardens in Japan, and grown in greenhouses, pots on balconies, sunny rooms, and commercial orchards.

Trees are self-fertile;[17] manual transfer of pollen between blossoms (even just by shaking the branches) can improve yield.

They are moderately cold-hardy citrus, but it is said of the seedless mukakukishu variety that trees should be taken indoors or wrapped in a frost cloth when temperatures fall below either freezing,[18] or 20 °F (−7 °C).

The fruit grows to 1–2 in (25–51 mm) in size and is harvested in mid-winter; in the Northern Hemisphere, this is November to February, depending on the local climate.

[12][7] Kishu mandarins became traditional Christmas gifts in Canada, a custom which probably spread from the Japanese immigrant community.

[24] Kishu mandarins are often propagated as budwood grafts,[23] like other citrus (many can also reproduce asexually through apomixis).