TO: Tyler Ludens
FROM: Eric Koperek = email@example.com SUBJECT: Cold Hardy Citrus
DATE: PM 6:00 Thursday 23 June 2016
(1) The most cold hardy citrus species is Trifoliate Orange = Citrus trifoliata. This is a small, thorny tree that grows even in the "deep freezer" of Mongolia and North Korea. Trifoliate orange is often used as a hardy root stock for grafted citrus trees. Trifoliate orange has small, sour fruits best used to make medicinal teas (very high Vitamin C) or marmalade. The fruits can be distilled or the zest pressed to extract a volatile essential oil used for perfumery. Trifoliate orange is a plant-and-forget-about-it tree. Stick it in the ground, throw some mulch around it, and water the tree occasionally. Otherwise, leave the tree alone. The fruits are good for "hydrotherapy": Liquefy 1 quart of fruit in blender then pour into sock (while holding over bath tub). Tie sock shut and drop in tub. Fill tub with hot water. Soak blissfully. Citrus oil vapors are comforting, especially good for relief of colds and influenza. This has been a standard treatment in our family Krankbuch (literally meaning "sick book" in German) since the early 16th century when Portuguese mariners first brought oranges from China to Europe (around 1520).
(2) Since varietal uniformity is not important in Trifoliate orange fruits, you can save and replant the seeds. Please note that ALL citrus fruits cross-pollinate easily so you cannot reliably propagate any citrus tree sexually (by seed). All commercial varieties of citrus are propagated asexually = by cuttings, grafting, or tissue culture.
(3) Keep DIFFERENT citrus varieties well isolated to prevent pollen transfer by bees. This means at least 1/4 mile (preferably more) for commercial orchards. For example, if you plant a sweet orange next to a lemon tree, your oranges may have a distinctly lemon flavor.
For more information about old-fashioned biological agriculture please visit: www.agriculturesolutions.wordpress.com -or- www.worldagriculturesolutions.com -or- send your questions to: Agriculture Solutions, 413 Cedar Drive, Moon Township, Pennsylvania, 15108 USA -- or -- send an e-mail to: Eric Koperek = firstname.lastname@example.org
Tyler, the Trifoliate Orange referenced by Eric may or may not be true citrus -- they are also known as Poncirus trifoliata and Wikipedia says "Whether the species should be considered to belong to its own genus, Poncirus or included in the genus Citrus is debated." However they survive well here in Central Oklahoma, although I've had considerable losses among young seedlings trying to overwinter them when temps get down to 12 degrees or so. Winter before last I lost all my seedlings in heavily mulched pots on the ground. This past winter I only had one seedling, which I kept safely in a dead chest freezer converted to a cold frame with water jugs in the bottom for thermal mass. I have personally visited two healthy mature fruiting trees in these parts (one in Hughes County and one down by Sulphur) so I know they can thrive once established.
Also hotly debated is whether the fruits have any particular food value. I like their strong aromatics and bitterness and I plan to make a bitter citrus liquer from them when my trees get to fruiting age. Their use for making marmelade is also somewhat controversial; one parody recipe on the internet calls for using one tiny fruit to many pounds of sugar -- and then discarding the fruit as the first step of the recipe. Somebody obviously tried the marmelade and did not like it!
The seeds are said to be best germinated fresh and not to tolerate drying out. However I harvested some fruits last fall and kept them in the fridge all winter. The fruits are now somewhat mushy and black, but when I pulped one under water in late May and planted the seeds, I got wildly successful germination, developing many dozens of seedlings from a single fruit. If you would like some seeds, I would be happy to clean up another fruit's worth and send them to you damp in a baggie in an envelope.
Possibly not the sort of cold-hardy citrus you are looking for. But I thought I would share additional info just in case.
Some might be pushing it a bit, and they are not as hardy as the trifoliate variety, but they are some of the second best. If can you find the right microclimate or get some fruiting then grow out the seedlings, they should work out.
I am learning citrus and avocado. Mine are in large nursery pots. They are moved outdoors as soon as weather allows and over winter in a simple sunroom/ leanto greenhouse (We are near Shawnee Ok) The sunroom is simple, built of 2x4 framing and glazed with corrugated polycarbonate from Lowe's home center - it meeds very little supplemental heat, the citrus tolerates light frost quite well (surprise me) This past year I started training them with flat backs, to make them easier to handle. I am thinking citrus is very worthwhile.
Tyler, It looks like you can buy finger lime seeds online. They are true from seed, to my knowledge. The fruit is pretty awesome, citrus caviar. They are pretty cold hardy. Finger lime is also HLB(Citrus greening) resistant.
I have a yuzu tree which has fruited for the first time this year. (Not gonna mention the scientific name, cuz there are a thousand different opinions out there and I don't know which is the canonical one.) It's supposed to survive a night or so of -9°C (a claim which I accidentally tested out last year). Are you still interested? Not sure how well it'll survive the trip from BC to Texas, but hey, it's probably worth a shot.