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Thomasville Citrangequat - Best All-Around Hardy Citrus? 


In late 1993, I visited what is now the Coastal Georgia Botanical Gardens for the first time. At that time it was called simply "The Bamboo Farm." While the Bamboo Farm was well known in Savannah, it was still pretty remote and largely undeveloped. The garden occupies the site of a former USDA research station (1919-1979), and during that time, many rare and experimental plants were planted there, including many types of Bamboo, Asian oaks, a now-record Formosan Sweetgum (Liquidambar formosana) - and one unusual citrus.


An old Thomasville in Savannah, GA

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As bad as it gets: after 11F in Dec. 2022
Full recovery, August 2023




I remember being struck immediately by this citrus, loaded with bright orange fruit (see photo). At that time, there were precious few citrus of any kind above Florida, this being not too long after the devastating freezes of the 1980s. I was enchanted, but I didn't think I could grow it more than 150 miles upstate - I didn't even know what it was!
However, that citrus lit a fire in my imagination. Was there some type of citrus - any kind - that I could grow? That led to much research on my part, and along the way I realized that the old citrus tree at The Bamboo Farm was a Thomasville citrangequat, a hybrid produced many years before by the USDA.
Thomasville was produced because it was noticed that while citranges were very hardy when dormant, they had the tendency to break dormancy very early in the spring, making them vulnerable to late freezes. The USDA crossed the citrange with a kumquat to induce delayed dormancy, which the kumquat has in abundance.
The result was the citrangequat. There are several varieties, but Thomasville is the most common and most famous.
This hybrid first fruited at Thomasville, GA (hence the name), but I have reason to believe that the Thomasville in Savannah may be a first generation (or at least second), making its inclusion at The Coastal Georgia Botanical Gardens truly historical in nature.
If I could grow only one type of citrus in the ground, I would probably choose Thomasville citrangequat. It grows true from seed and grows well on its own roots. It's hardy at least to 0F - temperatures around 10F don't bother it at all. Fruit are beautifully colored when ripe and taste like a pretty good lemon. Left on the tree, they become ripe out of hand in late winter and at that time taste like a common orange. The peel is hard, but sweet like a kumquat, so the whole fruit can be chopped up and easily made into some of the best marmalade you've ever had. If not frozen off, the fruit will hang almost indefinitely.

Other than the photo here of the old tree at the Coastal Botanical Gardens in Savannah, all photos are of my plants in Greene County, GA.

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