update on hardy citrus collection in PNW, April 2021

[Melenduwir]

What you've said is very true.  And there are a lot of domesticated plants (not just citrus) that reproduce in non-standard ways, especially with formerly non-self-pollinating crop plants adopting self-pollination as a strategy.

But in the long term, plants that don't prioritize crossing tend to be evolutionary dead-ends.

[SoCal2warm]

Everything I had outside was killed, with only three exceptions. The Yuzu bushes all died. Except for a tiny own-root Yuzu seedling that was very close to the ground, which doesn't even have any leaves but is trying to bud out some growth.
The Changsha mandarin survived and kept all its leaves, but it was planted in a more protected spot surrounded by bush growth from another plant (escallonia).
The Dunstan citrumelo survived and looks good now, though it lost nearly all of its leaves except for the branches very near to the ground. Even it experienced some die-back if a few smaller branches.
The last was a surprise, the Ichang lemon managed to recover and is sending out some good growth now, even though it was growing in a container. It suffered heavy damage. This Ichang lemon plant has not seemed to be very cold tolerant in previous years. Maybe it is inexplicable luck. The container was not too far away from the house. It survived while a Bloomsweet right next it died.

The other Yuzu plant which is located in the downtown area survived but lost all its leaves. The branches look a healthy green, with only a few grey damage areas on the branch farthest away from the trunk. It is now sending out leaf growth.

Both Ichang papeda plants appear to be dead.

July 1, 2022

[SoCal2warm]

Two small updates

One of the Yuzu bushes that I thought was killed seems to be sprouting a few tiny leaflets from its base, right above the graft line.

A seedling that I grew from US-852 citrandarin (poncirus x Changsha) seems to be sprouting up from the ground. I had presumed it was killed back to the ground by the winter, but it is possible my gardener carelessly wacked it down. It is planted in a shady colder part of the yard where hardy citrus has not seemed to do well.

It does appear that I see some green at the very base of one of the Ichang papeda plants, close to the ground. I don't know if it will be able to grow out.

[SoCal2warm]

Here is an update.

It has been a very mild winter (December 2023-February 2024) except for a brief period of moderate frost around January 9.

This picture was taken February 8. The Yuzu seedling is doing very good. Its leaves would probably look greener and healthier if it were not for an infestation of spider mites earlier in the year.

It's about 3 feet tall now (or just a little over 3 feet tall since it is sitting on a small mound).

The Changsha also does not look bad, and the leaves on the Ichang lemon look somewhere between not bad to good too.

None of them were covered this year.

[drymifolia]

It has been a very mild winter (December 2023-February 2024) except for a brief period of moderate frost around January 9.

Only "moderate frost"?? We had the most severe freeze we've had here since 2014, both in terms of absolute low (14.7°F here in my yard, 15°F at the official Seattle station) and also in terms of the duration of low temperatures (6 days where the high was around or below freezing). I had solid ground at least a couple inches deep by the end of it, couldn't break through with a shovel.

My unprotected yuzu seedling mostly defoliated (with some retaining only the first leaf segment), but the stems look fine:

[SoCal2warm]

Only "moderate frost"?? We had the most severe freeze we've had here since 2014, both in terms of absolute low (14.7°F here in my yard, 15°F at the official Seattle station) and also in terms of the duration of low temperatures (6 days where the high was around or below freezing). I had solid ground at least a couple inches deep by the end of it, couldn't break through with a shovel.

My unprotected yuzu seedling mostly defoliated (with some retaining only the first leaf segment),

To be totally fair, I was on vacation.
But Seattle must have gotten a colder wave than Olympia this winter because none of my citrus lost their leaves so far, and in fact the leaves still look good, the hue of green does not look too unhealthy.

According to a past weather record I looked up, it says it reached a low in Olympia of 12 degrees F in the very early morning of January 14 (2024), and the nights were cold the next 2 days due to clear skies. I doubt it actually went down quite that low where my plants were because the weather station is located in a colder part of Olympia. If the weather station says 12, then where I am it would probably have been more like 13.5 or even 14.5

[drymifolia]

According to the NOAA data it was even colder in Olympia than here, with 11°F on the coldest day and 5 nights in the teens. This first one is for the Olympia airport, the table is for the "Olympia Area," both from this page:

https://www.weather.gov/wrh/climate?wfo=sew

[Balance]

Here is an update.

It has been a very mild winter (December 2023-February 2024) except for a brief period of moderate frost around January 9.

This picture was taken February 8. The Yuzu seedling is doing very good. Its leaves would probably look greener and healthier if it were not for an infestation of spider mites earlier in the year.

It's about 3 feet tall now (or just a little over 3 feet tall since it is sitting on a small mound).

The Changsha also does not look bad, and the leaves on the Ichang lemon look somewhere between not bad to good too.

None of them were covered this year.

I live in a similar area and thus look forward to your updates to compare notes with. Do you have any other trees currently in ground that are doing well besides the Ichang, Changsha, and Yuzu? I believe I recall you having a mandarin at some point, did it die or is it still around?

[SoCal2warm]

Here is the Ichang Lemon. Not looking too bad. Right up against the wall of the house.




Here is the Dunstan citrumelo. The top branch which goes up (and is too tall to fit into the picture) is 5 feet and 7 inches high (170 cm).
It's doing very well, still has its leaves.




pictures taken February 26, 2024

[gordonh1]

Those are pretty small trees. I live in the area as well, and part of my strategy was to grow the marginally hardy varieties in a greenhouse and let them get to a certain size before planting them to endure winter conditions.  Somewhere, I had heard of a "rule of thumb", that the lower part of the trunk should have the thickness of a human thumb before being exposed to frosty weather.

Another consideration for varieties on the edge of their cold tolerance would be rootstock vs. own roots. I was going to try Yuzu on its own roots, and others as well, so that if the top dies back completely, it could regrow from the roots as the same variety.  OTOH, grafting to a Poncirus rootstock like Flying Dragon might make a good tree as well and maybe help with cold tolerance of the scion. I couldn't decide which was more important, so I'm doing both, at least for Yuzu.

[caladri]

As someone also in the PNW, I'd note that some commercially available sudachi sold in our region seem to be rooted cuttings, which is interesting — and mine has survived winters that knocked out whatever citrange Four Winds was using some year.

I'm skeptical of flying dragon in the PNW, given what I understand as slower overall growth and deeper dormancy. It seems worthwhile to me to have a bit of die-back now and then in exchange for being able to make the most of the short growing season. That's a matter of speculative personal opinion, though! But I spoke to one nursery owner who was outraged and couldn't believe that his trees grafted onto flying dragon (he ordered them that way) had hardly grown in one season. He was sure that wasn't how it was supposed to be, I'm confident because his previous orders has been grafted onto some kind of citrange.

It's a bit like people imagining that lemons are better to grow in the PNW because they're sour and therefore need less ripening and must also be more cold tolerant. Everyone on this forum, of course, knows better.

[gordonh1]

If Flying Dragon is too dwarfing a rootstock to use for in-ground Citrus in the PNW, I wonder what a good rootstock would be for us. I have Swingle citrumelo and C-35 available, as well as probably the standard species Poncirus trifoliata (not Flying Dragon). I have 852 citrandarin seedlings, too, but they're intended for fruiting, not rootstock.

For plants that I'm keeping containerized, I assume FD would be a good rootstock as we would want plants that remain of manageable size, since the containers need to be moved in and out of the greenhouse.

[Nemanja]

As someone also in the PNW, I'd note that some commercially available sudachi sold in our region seem to be rooted cuttings, which is interesting — and mine has survived winters that knocked out whatever citrange Four Winds was using some year.

I'm skeptical of flying dragon in the PNW, given what I understand as slower overall growth and deeper dormancy. It seems worthwhile to me to have a bit of die-back now and then in exchange for being able to make the most of the short growing season. That's a matter of speculative personal opinion, though! But I spoke to one nursery owner who was outraged and couldn't believe that his trees grafted onto flying dragon (he ordered them that way) had hardly grown in one season. He was sure that wasn't how it was supposed to be, I'm confident because his previous orders has been grafted onto some kind of citrange.

It's a bit like people imagining that lemons are better to grow in the PNW because they're sour and therefore need less ripening and must also be more cold tolerant. Everyone on this forum, of course, knows better.

I have a similar (and not so popular) opinion regarding rootstocks. I had a Nagami on Poncirus that suffered severe dieback whereas my Keraji on a Carrizo rootstock suffered no damage. I also prefer having a more vigorous rootstock that will push out more growth after dieback rather than having a "hardy" dwarf.

[bussone]

If Flying Dragon is too dwarfing a rootstock to use for in-ground Citrus in the PNW, I wonder what a good rootstock would be for us. I have Swingle citrumelo and C-35 available, as well as probably the standard species Poncirus trifoliata (not Flying Dragon). I have 852 citrandarin seedlings, too, but they're intended for fruiting, not rootstock.

For plants that I'm keeping containerized, I assume FD would be a good rootstock as we would want plants that remain of manageable size, since the containers need to be moved in and out of the greenhouse.

Species poncirus is less-dwarfing than Flying Dragon.

[SoCal2warm]

Here's a picture of the Ichang lemon again



May 27, 2024

You can see it's vigorously pushing out lots of new leaf growth, and the plant held onto its leaf growth from last year, which is still looking good.
It survived through the winter and was not covered. But it is planted up against a wall, and is in a protected spot. It mostly only gets morning sun in its location.

I'm happily surprised it is doing well. (Again, it is not Ichang papeda)

[a_Vivaldi]

I've been pleasantly surprised by the vigor of ichang lemon. I bought a seedling from Woodlanders last spring which grew decently the first summer. Given its size, I lightly protected it this past winter. Once spring arrived, it started growing like crazy.

March 16, mostly defoliated, some twig dieback.


May 30, now waist high, third flush in as many months.

[Mulberry0126]

I've been pleasantly surprised by the vigor of ichang lemon. I bought a seedling from Woodlanders last spring which grew decently the first summer. Given its size, I lightly protected it this past winter. Once spring arrived, it started growing like crazy.

March 16, mostly defoliated, some twig dieback.


May 30, now waist high, third flush in as many months.

I have some Ichang lemon grafts growing out into some handsome young trees now. They've been very healthy and most of the grafts took. Looking forward to seeing how they perform outdoors on Rubidoux trifoliate orange rootstock.

[SoCal2warm]

I've been pleasantly surprised by the vigor of ichang lemon.

It definitely has a fair to good amount of vigor and can grow well, and recover.

However, I will warn that from my experience, and judging by my observation of it growing in the PNW climate, it's not extremely tolerant of cold and can suffer damage.
It needs to be planted in a protected location, sheltered from winds, ideally close to the foundation of a building or brick wall, in zone 8a. And I get the feeling it wouldn't survive long term in the coldest part of zone 8a, bordering right on the edge of zone 7. But that's in the PNW climate. I can't say how it would behave in the US Southeast.

It's probably more of a zone 8b plant, but the climate here is solidly in zone 8a.

I remember one winter, the Ichang lemon, which was growing in a container outside at the time, did not do too well, ended up suffering severe damage and die-back, while a Bloomsweet in a container right next to it sailed through just fine. But later, the Bloomsweet planted in the ground in a protected spot ended up dying one winter, while the Ichang lemon in the container survived. (This was despite the Bloomsweet planted right next to a south-facing wall, and covered with a paper grocery bag during the coldest part of winter, with a gallon container of water set right up against the plant's trunk, in an attempt to help resist freezing)

The Changsha and Dunstan citrumelo are both doing well, have both grown out a lead branch over 4 feet tall. Both held onto all their leaves. I didn't really see any specific leaf damage, but the leaves did not really look the best at the end of the winter. The previous year's leaves are still satisfactorily healthy and alive though.

[a_Vivaldi]

Ichang lemon continuing to size up. It's past 3 ft now, and has filled out a lot better than it did after I first planted it last year.



As with last year, I'll be protecting this one for the first few harder frosts in early winter, and then any night below 20 F once it is fully dormant. There's a lot of tender new growth from this year that I don't want to lose.