PlantFiles: Japanese Hardy Orange, Bitter Orange
Poncirus trifoliata

I get several health orientated publications and there have been recent mentions of auraptine being a effective (even the most effective so far) therapy for breast (and on furthur search) colon, liver cancers. The fruit was extracted w acetone, but it could probably just be eaten, the skin seems to be the source. Low concentrations were effective in the lab to inhibit cell growth and cause self induced cell death. There was no effect on healthy non-cancerous cells.

Ref:

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T...

And

http://content.karger.com/ProdukteDB/produkte.asp?Doi=78001

I bet a dollar a drug co will patent this and charge thousands to cure people.

I have had this plant in the ground in my back yard for a few years now. Yes, it does have gnarley thorns on it, but mine grows straight up and we are careful when passing. It is in full sun for only a few hours each day, so I haven't seen any flowers on it yet. The foliage is filling out very well already, and its only the 5th of April.

I bought this plant because it was reported to be a Texas native citrus, and wanted a host for the Giant Swallowtail butterfly. For them it is working well. I have raised several butterflies from it so far. I hear the fruit are not very tasty, in fact they are bitter.

All in all, this plant is a great host, and would make a great barrier. The vendor who sold it to me said that a lady was having trouble with kids riding their bikes through her property and planted a row of them... Needless to say it fixed the problem. If looked after and trimmed up in fall, (with heavy long sleeves and gloves on, of course) this is a very nice member to have in my butterfly host garden. I am glad I have it!

I live in Atlanta, Ga, and have worked as a land surveyor since 1993. I have seen this plant growing wild all over the Atlanta area. I don't see it very often, but when I do, it is always growing in the woods, and I assumed it was a native plant.

I have some property about an hour East of Atlanta, and 2 years ago I discovered it growing fairly widely in the woods there. In all cases but one, I have seen it growing only as a single small shrub. However, one huge plant has many tiny offspring growing below it, but nothing impenetrable like a black berry thicket. The fruit here is sour, but also sort of semi sweet and perfumey. This year, I gathered the fruit and made a very tasty "lemonade" as did another commenter, as well as using it on fish. Next year I think I'll try something like "lemon meringue pie" or "lemon squares". I have also read that it makes a very good marmalade.

The previous commenter was right about there being something gummy or slippery in the peel or pith though.

I have read that in the UK, they make hedges with it. Perhaps its vicious thorns deters animals.

This plant is a noxious weed - one that I have been fighting for years. Wildlife transfer seed via digestion resulting in new plants in pastures and in the edges of wooded areas. Amazingly enough, this weekend I found a website for a nursery within 100 miles of my farm offering these weeds for sale at $10 each. I understand the value of this plant as rootstock and maybe as an ornamental (they certainly are strange looking) - but if you plant one, please eliminate the fruit as it ripens to avoid wild propagation.

I have actually taken the time to juice some of the little fruits. It is a royal pain, but the juice was delicious when made into a "lemonade". It tasted like a cross between lemon and grapefruit. There's something gummy in the peel that makes a huge mess of juicers and knives, though.

My trees are over 10' tall and are growing at over 12" per year still, so I'm not sure how tall they'll get in my central Virginia area. I love this plant. Yes, the thorns are evil, but the overall shape is nice and with the very pretty bark, and the beauty of the thorns, it's a lovely small tree even in winter. I have pruned off some of the lower branches each winter to make a tree shape; otherwise you'll have a bush. The foliage is also beautiful, tri-leaved and shiny. I get a few seedlings every year as volunteers, so if you want to propogate it, at least in my area, just dig up a few and transplant them. I originally got this plant from my mother-in-law, who got it from her father, who got it from a Chinese embassy representative in the early 1900's. It was very rare at that time. The only problem that I've had is that this year, from three trees about 10 years old, I had about three 5-gallon buckets of fruit to clean up!

Regarding the invasive nature of this plant: I have no problems in Virginia with it. I have had mine for 15 years now (I'm updating my previous entry). I get many seedlings right below the tree which are quite manageable since they're in a small area. However, I have seen no signs of any wildlife in my area eating the fruits, nor have I found any seedlings anywhere that were unexpected. I am also concerned about invasive non-natives and am waging war on two fronts against Vinca minor and Creeping Charlie, so I understand the other person's concern.

We have several of these outside our windows. They are evidently ungrafted root stock ("Flying Dragon") because they do not get any blooms or fruit, and very few leaves. They just grow tall and look menacing.

I am a Landscaper. A customer has one of these plants. 7-8feet tall 4 feet in diameter. It is in Bridgewater, NJ. One of its wicked thorns went right through my finger and then came back out without breaking off. We need to market these plant I notice that the Deer do not go near it. The fruit tastes terrible. Thats all.

This is a very hardy and fast-growing plant. It's also a prolific producer of bitter citrus fruit about 1-1/2" in diameter. In the 3 years since its arrival in our yard, our poncirus has grown about 12 inches per year and is now just over 6 feet tall. Many small (1-inch) white flowers in spring attract bees. Wicked thorns are up to 2 inches long. Trunk and stems are green when newly developed, then become gray with age.We don't have deer in our neighbborhood, but I can't imagine anything that bleeds trying to chew on this plant.

There are many sour (or bitter) orange trees in Corpus Christi in people's yards. Most of these are results of a hard freeze about 18 years ago that froze grafted orange trees to the ground, and the sour orange trees came up from the rootstock. They are not grown commercially here as they are in some places (such as in subtropical Lower Rio Grande Valley where nurseries grow them for rootstock). Sour orange trees are easily grown from seeds. Seeds should be taken from slightly overripe fruit, cleaned and dried, then planted in a pot in early spring. They are evergreen and in warm climates do well outside.

Search the internet for "sour orange" + recipes and you will find recipes for marmalade, marinades, and desserts. Leaves and flowers can be used to make tea.

This shrub grows easily in my zone in the Netherlands..so it can withstand heavy frosts and has survived winter 2002/2003 without no problems. Temps went down to -20 C and it grows even not at a sheltered place. The flowers are fragnant en the fruit is cute..look like small sized tennisballs. The fruit still smells a little after the perfume of the flowers but has also definately a lemonsmell when you cut them open.The fruit carries a lot of seeds and the flesh is more soft than the ordinary lemons. They are not edible but can be used for its cytrusbitterniss in marmelades.
Mind the long thorns that reaches 8 cm when you have children or pets. Birds love the fruit and the shelter they get from this shrub...unreachable for my neighbours cat...