Hybridizing cold hardy citrus to grow in the Pacific Northwest

Ichang papeda fruits, picked November 5, 2020, from a tree in Portland, OR
(pictures below)

The taste is halfway between lemon and Kaffir lime.

The outer peels are very soft and surprisingly halfway edible, only a little bit of bitterness, maybe just a little bit skunky in flavor.

The fruits are not really the best quality, and taste a little bit unripe, but there is nothing really bad about them. They'd probably go well with gin.


Much more detailed write-up:

I know some of you may have been curious about what Ichang papeda tastes like, so the following might be very interesting to you. It is of course not easy to describe in words how exactly something tastes like, but I will try to be very careful and descriptive and give as many details as possible.

There is a tree in the Hoyt Arboretum, in Portland, and saw the Ichang papeda tree there. It's up growing against the wall of the visitor center.
The location of the Arboretum is within the city, but on a mostly forested little mountain ridge inside it, and it is at the top of the mountain.

They also had a Wollemi pine plant that I noticed. Getting off-topic for a moment, the Wollemi pine looked like some of the top had died back, perhaps due to the previous winter, but overall it looked like it was surviving and doing okay. It didn't look like it was ever covered, and it was at least 15 feet away from the building.

The Ichang papeda tree is about 6 feet tall, and there was a fair amount of fruit on it. Maybe 40 percent of the fruit looked like it had dropped. Half of the fruit looked like a ripe yellow, or very close to being ripe, but the fruit size was pretty small. Maybe not much bigger than poncirus. So maybe in this climate the fruit does not have time to grow to its maximum size, or maybe it is still too early in the year (October 6).
So it is possible the fruits I tasted might not have been fully ripe.

The tree itself looks like it is doing well. I could not see any signs of the base of the tree being grafted on to anything, although I cannot be entirely sure. So it might be own-root. The leaves looked a healthy color.

The fruits I tasted were not much bigger than normal Poncirus trifoliata fruits. Although Ichang papeda fruits are supposed to be bigger than that.


The fruits smell similar to lemon, but deeper smelling, maybe almost a little bit resinous woody smelling (entirely in a good way). It's a beautiful fragrance, at least in my personal opinion.
Something about the fragrance smells just a little "off", in a way that sort of reminds me of kaffir lime. Maybe even almost the slightest bit "skunky" (but I would not say in a bad way).
The fragrance is very similar, in a way, to Yuzu, except without the sour orange type of fragrance and without the "spiciness".

(And some of the deepness almost reminds me a little bit of the deep aspect of the smell in Satsuma mandarins, though it would be a stretch to say it smells like Satsuma)

I can eat the rinds and peel of the fruits with little difficulty. I would say they are about as edible as mandarinquat, but maybe with just slightly more bitterness. Pretty similar to a kumquat hybrid or to citron, more like citron in flavor.

The flavor of the fruits is somewhere between lemon, citron, lime, and kaffir lime. But a little bit of bitterness. Still edible though. (Definitely nothing like the awful flavor of Poncirus trifoliata)

The inside juice segments are not very big, but they are decent enough. It kind of reminds me, not surprisingly, of a Yuzu, a little bit dry, not very juicy. But enough to be edible, if we are talking about foraging or a survival situation.
The inside kind of reminds me of an unripe lime, I would say would be the best description.


I also did not notice seeds in the fruit. There was maybe one shriveled up seed that does not look like it will be viable. But then there are tiny little orange gel spot segments where the seeds should be, in each segment.


Something about the aroma of these fruits seem to go very well with Bombay Sapphire East gin.


I am actually a big fan of these fruits. But that is just my personal opinion. I don't want to get anyone else's hopes too up. I am a huge fan of sour-aromatic things like lemons.
I mostly like these little fruits due to the unique fragrance, which is sort of comparable to Yuzu but more on the lemon or citron side.

I'm pretty sure the majority of you will not like them as much as I, so take that into consideration.

(These are of course like a sour lemon and worse fruit quality than a normal lemon, so many people are not going to find these to be edible, except for the more adventurous types of persons who like tasting strange things)

However, I do have to concede one thing, and that is that after eating a whole fruit, they do not really sit the best in my stomach, and afterwards I am burping up a sort of skunky taste, which I did not really notice so much while I was eating them. It's like they have an "off" flavor that only kicks in a minute or two after you eat it, after you have already swallowed. But I did eat the whole fruits with the peel and rinds.

Parker Turtle wrote: That is, if any of you are even able to get your hands on these varieties, which can be very difficult.

Thank you for your experiences.  Could you share where you sourced yours?  I know that One Green World offers Yuzu and Sudachi.

picture of Yuzu fruit I picked from the tree, cut open

Actually, the flavor isn't that bad, like lemon and a sour Clementine, although it's kind of dry, not the most juice, and it was very seedy. I ate half the fruit.
The peel of the fruit is also soft and mostly lacks bitterness, I almost kind of enjoy nibbling and taking little bites out of the peel.
If left on the tree very long, the fruit almost develops a very slight guava-like nuance to the aroma.

here's a picture of the Bloomsweet, Olympia, WA, climate zone 8a, November 3, 2020

Parker,

Great topic and thanks for all the good information. I am in 7a so I figure I will at least need a temporary cover to use in conjunction with a microclimate to grow anything more than Trifoliate Orange. We regularly get temperatures into the teens here, single digits are rare but possible.

I was considering having cold hardy citrus either growing alongside a south facing wall with a temporary cover for low temperatures or just buying/building a conventional-ish greenhouse. Keep the citrus either dwarf varieties and/or espaliered to fit either scenario.

Hey there,

Curious, any updates on your endeavors?

I'm on the hunt for ichang lemon sources somewhere on the west side of america if there are any. I found a nursery in SC that has some but the shipping is likely going to be pretty steep. So far in ground I only have a yuzu. I've started 2 owari satasuma from seeds and they're getting close to the point where i could plant them in the ground. Maybe this winter I'll chance one of them.  

Wow!  Kabosu!  I’ve been looking for one forever but thought they do not exist.  Even sent UC riverside a request to reintroduce.  I have Yuzu, shikuwasa, and sudachi but live in the Bay Area, California so do not have struggles with the freeze.  My interest in Japanese citrus comes from strictly a culinary perspective as they go well with seafood and certain soups. Gives me hope they might be available down the road.

Do you have an update on how your trees are doing this year?

Good stuff, glad I found this thread... I live on Vancouver Island zone 8a-b in Courtenay... I've been germinating seedlings and letting the surplus face the winter in an unheated greenhouse. In 3 years I've amassed quite a collection by germinating seeds from store-bought fruit, but only so much that can fit into a small truck, and the majority are in these red plastic cups. I managed to isolate a handful of survivors, with the best performing survivor a texas red grapefruit seedling.

What we look for are leaf retention and recovery rate, and the grapefruit had both qualities. I had a Meyer lemon survivor with no leaf retention but with a successful recovery however, only a fair one, as the growing season is ending. More than likely a second winter will be needed to see the long-term success rate, which I can see is dubious in some first winter survivors, so these ones will be kept in an unheated garage over the winter to keep their genetics going a bit for further stress testing.

Definitely don't waste these seeds, you never know what you get since citrus is so diverse.

Glen Parrish wrote:Good stuff, glad I found this thread... I live on Vancouver Island zone 8a-b in Courtenay... I've been germinating seedlings and letting the surplus face the winter in an unheated greenhouse. In 3 years I've amassed quite a collection by germinating seeds

Welcome to Permies Glen and thank you for sharing your experiments! Growing some hardy citrus is on my wish list for hopefully the near future! I plan to start with some named varieties but I think I'll start saving seeds too!

I have an unusual citrus tree in East Texas, zone 8A in a rainforest. Neither ice nor snow harm it in any way.  It does well in 115°+ to -17°F, produces fruit every year & self seeds. It is a Trifoliate species, classic 3 leaflets & white highly fragrant flowers. The fruit begins green & appear like perfectly spherical limes. By mid summer they turn yellow & become fuzzy like a peach. The fruit is not yet ripe. Late summer & into fall, the fruit loses most or all of the fuzz & gets splotches of brown over the yellow rind. The thorns can be 8- 12" long but most are smaller. They taste just like lemons but are strange. We have used them in iced tea & as lemonade & they are wonderful. There was a neighbor many decades ago who traveled world wide collecting plants & seeds & maybe she brought these from an Asian country. We were told they were Mock Oranges when we moved there 50 years ago, but they do not match that description nor any other that I know of. As a side note, our home there was built in 1834 & is currently 190 years old & we have hundreds if not thousands of these plants mostly along an intermittent creek or in the nearby woods. They are perfectly fine growing in complete shade but do well in any light.
As a teenager many decades ago, I wanted to lighten my hair. I juiced a dozen or more of these & put it on my hair. It instantly turned into a tar like substance that quickly & fortunately washed right out with shampoo.
If I graft improved Meyers lemons or some limes onto these shrubs, will it help them to become more cold hardy?

I would love to somedday grow lemons and limes here, as apparently they can be successful in zone 8, not just in anicdotal situations, but there are some proven varieties.  Someday.