Ive been eating some imported Mandarins the last couple of days, and I cant seem to bring myself to compost the seeds. When I look into growing Citrus in this zone 6-7 on google, or I ask around, I typically get the same answer:
“It won’t work in your climate. Its a waste of time.”
But Im getting deeper into the adaptive mindset, and I keep questioning if this is one of those things that everybody thinks is impossible, but might actually work out with enough time, space, and dedication.
If I was to plant 100 random imported store bought citrus seeds, how many might survive the winter outside?
How about 1000? Or maybe 10,000?
What do you all think?
Surely starting with the right genetics will help the odds be in our favor.
The goal being to have a tasty, juicy, sweet, productive frost tolerant mandarin-orange like fruit that can be grown outside without protection or coddling.
I would sow seeds of poncirus trifoliata, and adapt them for the hardiness you need, and then use them as rootstock for the citrus species (mandarine, orange) you would like to eat.
Poncirus trifoliata is already frost restistant , up to zones 9 so you have 2 more zones to work up.
I wouldn’t start with store bought, which tend to be from the warmest parts of the world, and instead try to source seeds that already have some cold tolerance. There are some crosses with poncirus trifoliata as well as some traditional citruses that do have a lot better cold tolerance, even if they aren’t as far as to do well in your climate yet. From what I have read, those more cold tolerant aren’t as palatable (even the ones that aren’t crosses with trifoliata), but it’s probably a better place to start with something that has a chance to survive in the first place, and only later worry about taste.
For an easy source of relatively cold tolerant stock, Baker Creek has trees producing in an unheated greenhouse in Missouri and has material for sale. I think they are using Japanese stock.
I also have a rustic edible (more are non edible) citrus landrace project underway .
for this I started from already rustic crosses bought with which I try cross pollination
I bought:
eremorange (Citrus glauca x Citrus sinensis)
ichangensis x sinensis (Citrus ichangensis x citrus sinensis)
cintrangequat ‘Thomasville’ ((Citrus sinensis x Poncirus trifoliata) x Citrus fortunella)
Yuzu (Citrus junos)
Kabosu (Citrus sphaerocarpa)
from this group of breeders I have a significant number of possibilities of crosses.
We could make exchanges I am still looking for Sudachi (citrus sudachi), US119 ( Poncirus trifoliata x (Citrus sinensis x Citrus maxima))…
if you want to get a glimpse of what it is possible to grow citrus with cold you have this good video :
Ok, how about 1 in a million random store bought fruit seeds?
Is there any chance for some deeply hidden gene to eventually come out and reveal itself?
I don’t think ill be purchasing any trees and having them shipped out here anytime soon. At least not until Im actually making enough of an income to justify spending money. My thoughts are more about using a relatively free and already available resource that would otherwise be composted, and instead put it somewhere that the genetic lottery can be played.
I guess if nobody can make an educated guess, then the only way to find out is to try, and keep trying.
If I do try then will it end up being 1 in 100?
1 for an entire lifetime of saving every citrus seed and sticking it in the ground?
The fact that there isn’t one already available tells you all you need to know. It’s not like it’s for lack of trying. In practice 1 in a million might be a crude underestimation. Adaption rarely happens in strides, but is more like small steps. If you choose carefully stock you start with, you might have 1 in a million chance.
You might want to read everything you can about this before getting too far. There’s a Cold Hardy Citrus forum at tropicalfruitforum.com where people who are interested in pushing the cold-hardiness limits of Citrus discuss their projects and progress. You could possibly connect with people there who have the most appropriate genetic material to start with.
For example, there’s a retired plant breeder in Pennsylvania (zone 6), who grew out something like 20,000 seedlings of an F2 hybrid between trifoliate orange (Poncirus trifoliata) and an orange. Based on theory, the F2 generation should demonstrate a small percentage of offspring that have the same hardiness as the original Poncirus, but with some Citrus traits as well. In his experiment, it was a pretty small number, maybe about 100 out of the 20,000, that survived a trial outdoors unprotected and these have matured or are in the process of maturing to produce further generations of seeds that maybe could be the start of further projects, maybe crossed with other Poncirus hybrids to create different genetic lines for further progress.
This was a huge effort and doable for him based on 100% dedication to the task, and sufficient facilities and land space. That wouldn’t be possible for all of us, but we can benefit from what these breeders are doing and maybe trial their products in our different climate zones.
What is realistic is for someone in zone 7 and 8 to grow out as many seedlings as they can from the results of previous breeding efforts, with the intention of selecting and improving the fruit qualities.
Regarding mandarin oranges specifically, the hardiest of them like Changsha could be grown in zone 8 and maybe tried in the milder parts of zone 7. It could survive down to between 5 and 10 F.
A reasonable breeding project to create edible mandarins for zone 7 and 8 would be to take Changsha and/or Poncirus/mandarin hybrids (called citrandarins), do hand-pollination, and grow out seedlings. With the citrandarins, you have some palatability issues with bitterness inherited from the trifoliate orange that you would want to select against.
This is exactly why I start from plants already known for their hardiness and taste.
Because even if you leave from poncirus that you hybridize yourself with the lemon tree of your neighbor, or the bitter orange tree of your grandfather… you can spend the rest of your life looking for a seedling that is hardy and edible, because 99.9999% will make you fall your tongue and teeth.
Lee Angold ou are a little more pessimistic about the hardiness, but all the trees I have are resistant to zone 7 or about -12°c (10°F) to -15°c (5°F) only if they are grafted on poncirus.
I understand that rustic citrus can be hard to find or expensive in some countries. Here we find them at about 15 euros from Italy, and 3 or 4 feet are needed to carry out this type of project.
The Soviets had carried out this type of project that you describe Arthur during the Cold War. They asked the population to bring back their lemon pepins in number. They planted whole fields, and eventually found a few feet that instead of dying at -6°C died at -8°C. So they grew them in deep trenches that they filled with straw and snow in the winter, then rediscover them and pick up 4 lemons in the summer. Suffice to say that this work did not last long.
Arthur trying to get some poncirus fruit in a botanical garden this fall. Make seedlings to make rootstocks because these are the only possible under your climate. Then in 2 years you can go hunting grafts (you will send me a MP )
Not pessimistic, rather, I was replying to a comment suggesting that poncirus was only hardy to zone 9. Poncirus is definitely much much hardier than that!
I am in Canada (zone 5b) myself. One of my summer projects this year is going to be rooting cuttings from my (indoor wintering) meyer lemon’s poncirus rootstock that is sending out branches. I will grow it alongside my outdoor overwintering passiflora and properly alarm the neighbours!
I do suspect that success with overwintering more normal citrus in zone 7/8 really depends on specific climate - how many days are below freezing, and how many freeze/thaw cycles. I’ve seen mature orange trees thriving in places with some surprisingly cold snaps, but none in, say…Toronto (zone 7 these days). Wild fluctuations around the freezing point 7 months of the year are not a thing citrus is equipped for
pessimistic for the yuzu, it holds in zone 7/8 not 9
yes the poncirus holds in zone 5.
The big success is when we graft on poncirus that is deciduous, the sap no longer circulates in the winter, and frosts have less impact on cultivated trees that are resting. It would also seem that poncirus graft gives better taste to citrus fruits.
I applaud the resourcefulness and ingenuity of this idea. Great minds and all that jazz…I have some seeds from the best grapefruit I’ve ever sampled in a jar waiting till I figure out how to hook them up in my 6A previously 5B climate. Your idea of the numbers game. Definite merit in my humble opinion. I’ve seen all kinds of things that according to the Big Ag experts shouldn’t exist. In the spirit of adaption and experimentation and sowing seed you already have in hand and dug the taste of…Why not? Right on!
Yes, the issue of apomixis (seed produced that is genetically identical to the parent) is super-important for choosing plants suitable for a landrace adaptation project! For example, you would have a very limited chance of producing a landrace by starting with certain well-known rootstock citranges like Morton and Swingle, because 90+% of the seeds are genetically identical to the parents. For rootstock, that is an advantage, because you can easily raise predictable rootstocks in great numbers. For creating a landrace, obviously we cannot make progress with identical genetics, we need to have genetic mixing and exploration of new combinations.
That’s why I’m working with citrandarins, which have a much greater chance of seeds that are the result of sexual reproduction. There’s one with a number, 852 citrandarin, that is a product of the USDA breeding programs, and is made available as a rootstock. Seeds from this citrandarin have shown variation in cold hardiness, which could be a good start on a landrace.
Logees sells a frost tolerant mandarin. I just got one of the plants and hope to get some fruit from it here in an unheated greenhouse in zone 6a. The description:
"Satsuma Mandarin Orange Tree ‘Frost Owari’ (Citrus unshiu)
‘Frost Owari’ is a favorite satsuma mandarin with medium-size, deep orange fruit that are seedless, sweet and juicy with easy-to-peel skin. Originating in Japan, it’s a vigorous grower and highly productive fruit tree. It makes an ideal container plant for northern growers since it only reaches 10-15’ tall in outdoor gardens but can be maintained at a much shorter height in containers. The fruit starts to ripen in late fall and it’s usually ready for harvest in early winter. Satsuma mandarins are cold hardy citrus being able to withstand temperatures into low 20s°F and even into the teens for mature plants. "
This also brings up the subject of better cold tolerance in older citrus trees vs. seedlings. I saw this first hand this winter when my grapefruit plants died back during a very cold period, but are now lush with new growth from the woody stems. Seedlings would have died. So using seedlings to determine cold tolerance may kill off plants that might otherwise do well as adults.
in the things to take into account also to start with citrus, it is necessary to choose certain rustic varieties but also to look at their date of fruiting and maturation that must occur before the cold of your zone. The fruits are less hardy than the plant. So at home for example I have to choose citrus fruits that fructify early between September and December, the cold can occur in January February.
You all have some really awesome stuff going on! Wow! What caught my imagination when I saw this post was something along the lines of a Johnny Appleseed story line. Around 7 minutes into the video if pressed for time. Planting a whole bunch of seed could result in bringing out/ turning on something phenomenonal including but not limited to cold tolerance. Additionally the cost of planting a free seed in this beautiful World of abundance? I’m into it!
Really phenomenal to hear all the fun plant projects going on!
852 is the citrus I’m starting with here in Michigan. I’ll post updates once I go through a winter or two and see how well the seedlings perform.
Is there any other particular variety or hybrid you recommend for crossing when the time comes? Should I try to add some yuzu genes? I’m just trying to give myself the best chance I have of eventually landing on something decent
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