To start on a positive note, an update on the recovery of the Callistemon 'Woodlanders Red' at JCRA.

Here's how it looked at the end of April:

And now:

So while the outer twigs appear dead for good, there's lots of growth from the thicker stems in the core.

I had a Callistemon citrinus that limped along for a few years, coming back after cold injury every winter, but it never thrived and finally gave up the ghost. My list of Mediterranean failures is lengthy, as is my list of alpine failures. But I keep trying, and the lists keep growing. Intermittent reinforcement is a powerful thing.

My only success with Bottlebrushes is with a potted Callistemon 'Little John. Every other version planted in the ground suffers except during mild winters. Even the one C. citrina planted in my most sheltered flowerbed got damaged this past winter.

How long have you had your potted Little John, and how big is it? I'm always tempted when I see one at the nursery but have thought it would quickly get too big to grow in a pot.

I think I bought it last spring and overwintered it in my greenhouse but it may be two years old. It has only grown like a coupled of inches so far. I have it in a large pot. It bloomed last year, but didn't get completely covered in blooms. I was hoping for big things this year but so far it has no buds on it. The entire bush is maybe 2+ feet wide and a little under 2 feet tall. I saw a lot of them out in Las Vegas last winter and none of them were any bigger than my plant.

As mentioned in the "cold hardy succulents" thread, local eucalyptus trees, even well established ones, suffered significantly this past winter. Now that there is a more suitable thread for this topic, here are more details.

We had one particularly impressive specimen of Eucalyptus cinerea in our neighborhood (near Southpoint in Durham) that never showed any signs of damage, but was badly burnt this winter:

Since the time those pictures were taken (end of April), it was cut down and is resprouting profusely:

Some of the new growth seems to be drying out (on the left side), so it is still uncertain how robust this recovery will be.

We had two E. cinereas raised from seeds and planted out in 2012: 8 and 12 ft tall and 1.5 and 2 inch trunk diameter, respectively. They always suffered complete leaf browning but recovered fully along the whole trunk and thicker branches. After this winter, they only grew a few fresh twigs at the bottom of the trunks, but this new growth died out after a few weeks. Here's the shorter one:

Since E. cinerea is considered a USDA Zone 8a plant, our current plan is to try the more hardy E. neglecta, often reported as Zone 7a and successfully grown in Northern Virginia. We got seeds from CactusStore.com and are currently raising seedlings. We will also try two other species, less known for their hardiness in the U.S.: E. subcrenulata, believed to be a good houseplant (unlike E. cinerea) and E. websteriana, most likely less hardy but also to be tested in containers.

For the sake of completeness, we also had an E. gunnii, distinguished by smaller leaves than E. cinerea. It was killed as a result of a premature attempt to coppice it (at about 1.5 inch trunk diameter) to make it more bushy, from which it didn't recover. We may re-try E. gunnii again - there is a variety named 'Azura' that is reported in Germany and Austria to be particularly cold hardy, but we haven't seen any sources of its seeds in the U.S. or any reports on its hardiness here.

Wow, cool update. I wonder how the big E. neglecta at PDN looked after this winter?

Anyhow my semi-quick opinion on Eucs based on ones I've tried: E. neglecta is certainly one of the hardier, and more growable ones. But I am in a very windy microclimate, on a ridge along the upper Chesapeake Bay. It hasn't gone below 0F since I moved here, BUT, the winters can be extremely challenging for some BLEs. Even a hardier cultivar of C. japonica, for example, will be incinerated if exposed to the morning sun in winter, after long nights of winds howling so loud it is like a freight train going by. I had E. neglecta and E. lacrimans in my garden at the same time, and during a slightly cooler than normal winter spell at some point before the polar vortexes, (maybe 2008?) the E. neglecta was totally trashed - basically killed - and the E. lacrimans was completely undamaged. They were both in a relatively exposed site. Low maybe 5F.

Unfortunately, I had planted the lacrimans near the base of a part of my driveway, and didn't realize how wet it would get in a big autumn rainstorm like we often have around here. Next year, 14" in roughly 72 hours caused it to get root rot and die. I consider that foolish planting location one of my worst gardening mistakes ever! The tree where Ian got seed in the PNW was cut down and the very rare species became unavailable in the US nursery market for years.

If you compare, E. lacrimans grows in a colder area than E. neglecta, and one of the coldest parts of AU, period. Right near their "tree line", which there, is inverted. It's the highest valleys that collect the coldest air!

(Later on, btw, had an Eucalyptus parvula get up to about 15-20' in a somewhat more sheltered area; it was killed to ground in the first polar vortex. It re-grew vigorously, I was sure it was ok. The 2nd polar vortex finished it off! I'd say E. parvula is roughly as hardy as E. neglecta, and slightly prettier to my eyes.)

Ian thinks he is going to have them again soon, so I will definitely be ordering some. And so the issue for growers in the south is all of these alpine species are coming from very cool summer climates, and are prone to root rot when things are too hot and wet. Fortunately compared to other plants from such high elevation areas of the world, like the cinnabarina subsection rhododendrons, they are not SUPER prone to root rot. One just has to be very careful. (and I doubt E. lacrimans will grow in New Orleans, but there would be other species to grow that far south!)

Main negative about E. lacrimans: the foliage is almost scentless! A trait shared, in the conifer world, with the best fir for the south, Abies firma. Only fir with almost no foliar odor!!!

BTW I think there could be a lot of opportunities for hybridization in the future, assuming they will cross. I want to try to cross E. lacrimans and E. parvula. They will compliment in a lot of ways like leaf size, speed of growth, and foliar odor! I see in the world of rhodies that F1 species hybrids have a lot of vigor and 'garden toughness' compared to their parents. Unfortunately, my replacement parvula - second year in ground - was killed by January 2018, which had the coldest first week of January in Baltimore history. And, unlike the polar vortex winters, I had no snow cover! The soil froze deeper than it had in either of those winters and it was just too much for it. I wonder if I could have saved it by dumping a huge pile of mulch on it with my front end loader, but oh well!

Ian also might offer E. delegatensis soon, which, crossed with E. lacrimans, could offer large size in the offspring. They are the last giant Eucs one sees when ascending into the Snowy Mountains, many of them over 100' tall at elevation over 4000'. Probably only 8a hardy if that though...but probably the hardiest Eucs that get that big.

Even though I'm not a "Carolina Gardener" it's cool to find a forum on GW where people are discussing these kind of plants!

Anybody have an Olea europaea 'Arbequina' planted outdoors that survived last winter in our area? I recently saw one in a pot in Morrisville that was in fruit and now I really, really want to try and grow one, but I'd like to do it outdoors if possible.

Karen, this is a good opportunity to integrate the previous discussions on Olea europaea into this thread. We are still placing our bets on seed-grown species (obtained from Lorabell, still in pot).

Les, did you get cuttings to root from your seed grown olive?

They are on the to do list for late summer (semi-hard) and winter (hard). The plant has finally grown enough to start trimming it and make it bushier. We can put you on the waiting list for any extras.

Davidrt28, great to see a kindred spirit like yourself join this thread, and hopefully others. There are hardly any discussion groups on this topic so we should not limit ourselves strictly to the Carolinas, but would welcome contributions from any neighboring areas where their experience is still highly relevant, such as yours.

There are lots of subjects in your posts worth followup and discussion and we'll be responding to them in due course.

Davidrt28, here are the temperatures at the beginning of Jan 2018 at the RDU airport, not far from JCRA:

(the columns are: date, max, min, avg, departure from normal).
The duration of this cold event was much worse than the previous two years that also tested the boundaries of Zone 7b.

Certainly, Australian plants from the typical Mediterranean climate may not have adequate cold hardiness for such temperatures. Those that do well in our area come from more extreme environments, such as mountains or deserts. But, firstly, "extreme" in Australian terms is still very moderate as their coldest areas with vegetation are barely Zone 6. And secondly, even those only moderately cold areas are not necessary the direct sources of the plants available here, as they often come via California.

Unlike the trends that popularized cold hardy palms or succulents, which systematically tested and selected a number of reliably hardy species and special varieties over the last three decades, no comparable effort has been done in Australian plants, where the available selections are mostly whimsical and by trial and error. Australians themselves have little motivation to select and promote in nursery trade the cold hardy isolates and U.S. pioneers and explorers like PDN or JCRA have been focused in other areas.

So it is very interesting to hear your observations, in particular about something so rarely mentioned as E. lacrimans. Many enthusiasts, such as ourselves, would be very interested in testing those rare candidates - which should be simple as they grow so fast from seeds - but the seeds are not available. We ran into E. subcrenulata through seeds from J.L. Hudson. There is very interesting information about it in its profile at DG:

"The Alpine Yellow Gum is interesting as it forms a cline (superspecies)
with two others, namely E. johnstonii from lower elevations and E.
vernicosa from higher elevations. E. subcrenulata sits somewhere between
and forms a moderate to fairly large tree ultimately, whereas E.
johnstonii is larger and more vigorous while E. vernicosa is a
remarkable dwarf leathery leaved shrub and is just about as hardy as any plant can be!"

So it would be very interesting to explore that even hardier species, E. vernicosa, with the added benefit that it may be a smaller shrub.

Hopefully, there will be more suppliers of seeds of the rarer eucalyptus species and we should definitely make an effort to spread the information about their availability.

We were not aware that there was any eucalyptus, in particular E. neglecta, at PDN, but we don't go there very often and don't know Tony's collection of plants too well. Can anyone of the regulars there tell us where it is located and maybe post pictures?

Ironically, we were just there at the July Open House buying another cold hardy Mediterranean plant, Nerium oleander 'Mathilde Ferrier', as several of our efforts to grow outside what was sold to us as N. oleander 'Hardy Red' have been unsuccessful.

I am trying a 'Mathilde' bought at Camforest. First - and possibly last - Nerium I will try. My reasoning is I know from people who lived in VA Beach that even in 1985, temps < 0F throughout the state of VA, they recovered from the roots. So they are generally tough plants, it seems. Might as well try the hardiest one in a very sheltered spot. I think mine will need at least a couple mild winters in a row to get well established. But we have had those: from 2006 to 2013, I was actually averaging just a little above 10F (for average annual minimum). Not so since 2013! I was about 2 or 3F in the first two PV winters, and right around 0F in January of this year. All properly established camellias, for example, have been fine. Including the very special 'Aida', the hardiest C. X williamsii. (which Dave Parks told me didn't grow well for him...strange...but he thought it was maybe a little too hot for a plant bred at Longwood. LOL because people in maritime climates think we are all in a hot summer steambath from NYC to Miami...and that's true but there are regional differences in the summer climate along the east coast. Even where I live, you see a lot more rhododendrons in full sun, than in the suburbs of DC. Also, "northern" plants like Aesculus hippocastanum. At any rate, would love to know if anyone in NC has an 'Aida' in their garden...maybe it just didn't like something about conditions at Camforest)

Fantastic recovery of Eucalyptus camphora at JCRA (in P01):

We were going around it in circles for 5 min unable to find it because we were looking for the bare stub we remembered from spring. The stub is still there but with 7 trunks 6-8 ft tall.

Also great recovery of Callistemon 'Woodlander's Red' in X02 - all this is new growth:

On the other hand, the recovery of our neighborhood Eucalyptus cinerea has dried out and died off:

That last photo makes me feel sad. I wonder who planted it in the first place, and will they/or the current owners replant?

Several interesting dwarfs in the Mediterranean section of the USBG Conservatory.

Callistemon viminalis 'Little John':

Olea europaea 'Montra' (Little Ollie):

Cupressus sempervirens 'Tiny Tower':

Also, Eucalyptus globulus subsp. bicostata (not a dwarf) grown in a big (~2 ft) pot in the garden:

FWIW Eucalyptus lacrimans is now available at Desert Northwest. In my experience with Eucs, it is by far the hardiest. But as I said "up thread" it will need especially excellent drainage in the eastern 2/3 of the CONUS. I plan to put one on a mound of a soil, that is already on a slope. Really ensure there is no way it can stay water logged. He also has E. neglecta which is definitely in the top 5 hardiest and the only of those that is known to grow well in the south.

If so, then they need to update their Web pages. The only two eucalypti listed in their mail order catalog are E. coccifera and E. regnans. Different species, not including E. lacrimans, are listed on their local sales list, but it is from 2014.

Oh that Ian. What are we going to do about him LOL.

He is terrible about updating his web site. This is what he has in his pdf list from 1 month ago:

Eucalyptus dalrympleana
Eucalyptus neglecta
Eucalyptus nobilis [Nundle, NSW]
Eucalyptus olsenii

IIRC the E. lacrimans were a little small and he won't add them to the official list until next spring, but one can ask for them now. I will post a picture of the ones he sent. I'd rather get them small, myself.

Eucalyptus dalrympleana might be worth trying in a solid 8b place like the Outer Banks. He doesn't think the other 2 are very hardy at all, but is offering them because they are rare and could be interesting to collectors in CA and coastal Oregon.

Thanks for the catch, Casa!

More details on E. lacrimans, in particular its relationship to E. pauciflora.

We've been trying for a while to propagate Callistemon 'Woodlander's Red' but have been unsuccessful to get cuttings to root on several occasions - many thanks to TriangleJohn for bringing them patiently several times.

However, we had much better luck propagating from seeds after we discovered a local specimen that flowered in the summer of 2017 and produced the characteristic woody capsules in the fall. We made two collections: in October and December of that year. Internet sources say that the capsules should open by themselves and spill out the seeds. This did not happen with the October batch and using the seeds from broken capsules did not lead to germination. However, the December batch - in spite of not looking differently from the previous one - did crack open by itself after 10 days in the house and spilled the seeds out. The seeds germinated after a few days with a high rate (because of the previous failure too many were seeded, resulting in a dense carpet of growth):

We started separating them in April to yogurt pots and then upgraded in June to 6 in long 2-3 inches wide tubular containers in which powdered juice drinks are sold. Here's how they looked in November:

They overwintered well in the house (good house plant) and will be grown for a few seasons in pots to build up woody tissue.

Interestingly, we have two seedlings that didn't get longer than two inches but still seem viable - further growth will show whether they were just retarded and will recover and grow larger or whether they are genetic dwarfs.

This brings up the issue of genetic variability of the seedlings, in particular with regard to cold hardiness, as seedlings of vegetative clones of hybrids don't come true to type. But the extent of variability is hard to estimate and may actually result in some of the offspring being even hardier. We could not find any reliable information about the exact origin of 'Woodlander's Red', in particular whether it is a hybrid obtained from seeds or a vegetative mutant (witches' broom).

Les, I think that's the same as 'Woodlanders Hardy', which they have on their nursery website. It says they thought it was C. sieberi at first but when it didn't bloom yellow they knew it was something else. I've seen different websites speculate as to what species it might really be. You could try calling or e-mailing Woodlanders for more information.

Also, if you ever decide to cull, keep me in mind!

I stumbled across thread by accident. Gardeners everywhere push zones, don't we!

I was a little surprised to see the attempts to grow eucalyptus. Here in California they are considered an invasive weed, very destructive to local habitats, and worse, dangerous because of their high wildfire risks. They are our local version of kudzu. But I suppose that if you struggle to get them to survive, you are unlikely to have problems with them. And the fragrance is wonderful.

yeah I don't think they become a problem even in Florida...although some other Australian plants do.

.We could not find any reliable information about the exact origin of 'Woodlander's Red',

IIRC the personal notes of JC Raulston, which were posted for years on the NCSU arboretum website but no longer are, said it was bought from Woodlanders as "Callistemon sp." It was able to return from the roots after the devastating 1985 freeze in Raleigh, well below 0F. Hence it was sent back, perhaps, to Woodlanders as 'Woodlander's Hardy'. Or just renamed.

Problem with such plants up here is you need a string of mild winters to get them established at this end of zone 7 (zone 6 just a few miles north), versus their end. (zone 8 not far away) The Callistemon I mention above, and Nerium 'Mathilde Ferrier', were severely injured by my winter low of 4F, but will be OK I am almost sure.

Davidrt28, you had a 4F low this winter? We are preparing a new thread "zone 8b winter" about the unusual things in the garden because of the 17F low.

Karen, we can get you one of the Callistemon seedlings at the Swap. We are ashamed to confess that in a misguided attempt to speed up the growth of Orostachys erubescens obtained from you, we decided to keep it in the house over the previous winter and it did not recover afterwards, unlike the O. fimbriata already in the ground. So if you could get us a refill that would be great.

Les, I lost some of my O. erubescens this winter from all the rain, so I'll have to see how it recovers. If I can't take a division out for you this spring, I'll get one for the fall swap.

Our Mediterraneans are doing well, greatly assisted by the recent mild winters (not dropping below Zone 9).

Eucalyptus neglecta, started from seed in December 2017 and planted out in March 2019 is reaching 7 ft:

Laurus nobilis, planted out in April 2015 (suffered through two very cold winters) is about 3 ft tall:

To address our interest in cold hardy guavas, we rooted a number of cuttings at the end of September 2019. The cutting material was kindly provided by Tamelask ( https://www.houzz.com/user/tammy-kennedy ): enough for 24 cuttings of Acca/Feijoa sellowiana (pineapple guava, Z8) and 12 cuttings of Psidium cattleianum var. littorale (strawberry guava, Z9). Of these, only one A. sellowiana cutting and two P. cattleianum cuttings have successfully rooted, resulting in the yield of 4% and 17%, respectively. This confirms many reports that A. sellowiana cuttings are difficult to root, but clearly not impossible. Here's a picture from last fall - with the cuttings exactly one year old.

The plants overwinter very well in the house and already start growing there in early spring.

Feijoas have survived for me since 2010 including the polar vortex winters, but survive for me here in NE MD, means it gets enough defoliation and stem damage in a typical winter that it never seems to bloom. This was the mildest winter since 2006 so if they won't at least bloom at this point - never mind making fruits - they will be deaccessioned.

Note, too, that these were seedlings offered by Edible Landscaping in Afton VA; I seem to recall they said they came from a locally hardy plant that sometimes fruited but I can't be sure. In any case, it's possible I just got a couple seedlings that lacked the hardiness of their parent. EDIT: looking at their website now, they just say 'seedlings', so maybe not even locally sourced near the northern limit of its cultivated range.

Casalester- that's what john b has always said about feijoas; they are extremely hard to root. You are welcome to come get more cuttings any time if you want. The one i have in the ground is said to be self fertile - coolidge. At the moment i have another cultivar growing as well that we dug from the community garden when we had to move. don't know the cultivar but it is a cultivar and it's not coolidge. The strawberry guavas i have are both seedlings i believe. One produces better than the other. They are pretty easy from seed.

After a few winters of not freezing to the ground, the Callistemon 'Woodlander's Red' at JCRA is getting humongous: 5 feet tall and 8 feet wide:

I'm trying one in a sheltered spot. I made the unfortunate "mistake" years ago of planting one of these supposed hardy Callistemons just before 2013-2014...it might have been 'Clemson Hardy'. Well, you know how that ended! They are, of course, in the same family as Feijoas, and it's not a terribly hardy family!