The Flying Dragon Citrus tree, also known as Hardy Orange and scientifically as Poncirus Trifoliata is a cold-hardy deciduous citrus shrub.
The first time I saw a Flying Dragon, or Hardy Orange, I was in awe. Here I was in Western North Carolina, and I was looking at an orange tree. Or lemon. I wasn’t sure at that point. I had to do some research to see what this wondrous fruit was all about. It turns out they are pretty common around here and in many other places.
What is Flying Dragon Citrus?
The Flying Dragon is a cultivar of Poncirus trifoliata (created by Walter Tennyson Swingle, who also created many of the cotton plants still used today) that came about around 1914. Trifoliata means three leaves, which are present in most of the Poncirus. The fruit is smallish, ranging from ping pong ball size to a bit larger. It is fuzzy and has many seeds (get seeds here). The fruit yields about 20% juice, but the peel is what people use more than the juice. You can boil the peel in sugar to candy it, or make it into marmalade. It contains large amounts of pectin, so no additional gelling agent is needed. The juice is quite sour but makes a great flavoring. And the peel is bitter but lends well to jelly and marmalade.
Although it is not in the citrus family, some consider it a distant cousin. It does, however, contain some of the same compounds. The hardy orange, sometimes incorrectly called bitter orange, contains quercetin, an important flavonoid that aids in treating allergies, vitamin C, and pectin, a soluble fiber. There are many other compounds they are experimenting with, including deriving an anti-oxidizing agent from the seeds, much like Grapefruit Seed Extract. Another promising study they are conducting involves anti anaphylactic actions instead of using epinephrine. Watch for more news on this study!
Description of Poncirus Trifoliata
The Poncirus tree is actually more of a shrub. It is usually around 6-8 feet tall, but can sometimes reach 20 feet. It is deciduous, meaning that the leaves fall in the colder months. The blooms, which do smell a lot like orange blossoms, come out in the spring, usually April, and into May in the colder regions. Small, hard green fruit will follow. They will ripen throughout the summer to be ready in the fall, usually around the beginning of October.
Be aware that even a small tree may produce hundreds of fruit! They will fall if not picked and the seeds sprout readily the following spring. The tree itself is slow-growing but will fill out nicely as time goes by. The tree can begin producing fruit in just a few years.
Poncirus Trifoliata is Not Osage Orange
Don’t confuse this tree with the Osage Orange, which is not edible. That fruit is larger and looks more like a brain.
One of the things that make Poncirus trifoliata unique is the thorns. Many citrus trees have thorns, but these are large and thick. People use them as toothpicks and say they can even puncture automobile tires! Many birds have caught onto this and often build their nests in the tree branches. This offers protection from predators. For this same reason, Poncirus trees will often line a fence line. Most animals won’t go near them again once they get a feel from the thorns. I have some around my chicken coop to deter the local bears. I haven’t tried them on my goat fence yet, but that’s next! And most animals, like deer and bunnies, won’t eat them, so you’ll have the harvest to yourself. They have very few natural predators, like scale and aphids, so you’ll rarely need pesticides.
Poncirus isn’t picky about the soil it is grown in. As long as it isn’t very alkaline (limestone type soils) and has some drainage, it’s good. I have clay that I amend and the pH runs about 5.5-6.5. They do very well here! Growing zones are wide, ranging from zone 4 to 8, which is most of the US. In northern areas, like Minnesota (mostly zone 4), they may need protection. It is best to plant them in a small microclimate area, such as along a south-facing wall of a building.
The Future of the Flying Dragon Citrus
In addition to the studies above, the Flying Dragon (Poncirus trifoliata) is also in use as experimental rootstock for non-hardy citrus trees. Citrus is not normally cold hardy, but by grafting them onto the Poncirus trunks, they stand a better chance of weathering the cold. Crossbreeding is also in the works. The common orange, Citrus sinensis, has been successfully cross-bred with Poncirus to get the Citrange, a more cold hardy citrus tree. This comes from Swingle and Dr. Herbert John Webber, who also created the Tangelo. The experiments are promising to those in northern areas that only see fresh citrus that is trucked in over many miles.
Me and Tou Lee of Lee’s One Fortune Farm in Marion, North Carolina are also doing experiments. He and his family have brought rice to a region that is not typically hospitable to rice. We are also experimenting with edible cold hardy bananas, tea, and other things not normally grown here. Stay tuned!
Have you ever seen a Flying Dragon citrus (Poncirus trifoliata), or eaten its fruit? What did you think?