Razzlequat or Coachella Eremolemon

Citrus (Eremocitrus) glauca x ?

Hardy at least to 13°F, -11°C

There is a lot of confusion as to the origin of this variety.  It was named Razzlequat in the Oregon Exotics Catalog, which suggests one parent is a kumquat, but the catalog's author identified it as 'Eremocitrus x C. Limona Meyer'.[1]   Mislabeling continued in 'Hardy Citrus of the Southeast' Kumquat x Eremocitrus glauca[2] p.26.

Swingle called it a "Eremolemon [Eremocitrus glauca X Citrus limon 'Meyer lemon']." [3] and the UCR website takes its information from him [4]

It now appears that it is a cross with a grapefruit.[5]

Hardiness testing in Savannah Georgia showed it to be one of the hardiest varieties tested.   Surviving 13°F, -11°C with poor acclimation better than Yuzu and Ichang papeda.[6] Since Yuzu is considered to be hardy to 10°F, -12°C it should survive lower temperatures.  Perhaps it maintains dormancy longer than Yuzu and Ichang papeda when exposed to warmer weather. 

Plant is very thorny.  Flavor is sour. Very rare.

Pictures courtesy Virginia Fruit Grower
 

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