Hardiest Eucalyptus Tree?

[PalmTreeDude]

Are there any Eucalyptus trees hardy enough to survive on the boarder of zone 7a/7b in Virginia? If so, it is the hardiest?

[Bennz]

Some of the alpine species from the SE NSW/E VIC border  or the TAS highlands would be the best bet for cold tolerance.  But the problem you will likely have is that these species are also adapted to very cool summers, and are likely to suffer in hot humid weather. I think you will find this challenging! Nowhere in Australia has a climate as warm and humid in summer but also occaisonally cold in winter as USA East Coast.

 

As an aside, I'm in New Zealand. 20 years ago there was a lot of enthusiasm for a potential pecan industry here. Collectors went to USA to try to find the best genetics. The trouble was the pecan populations that occur in USA areas with summers as cool as ours need far more winter chill than we can give them, and don't produce here. The pecan genetics adapted to our degree of winter chilling come from the extreme south of the natural pecan range, and don't get enough heat in NZ to produce anything. Basically, it doesn't work. You will likely have the same problem in reverse with your search for eucs.

[TexasColdHardyPalms]

I am unaware of any that will handle zone 7 but there are a few that do well in 8B that I started to grow in the last year.

[NorCalKing]

I've never heard of any Eucalyptus that would survive there. Remember they're native to Australia. 

[Matthew92]

Check this article out. "Introduction of Eucalyptus spp. into the United States with Special Emphasis on the Southern United States"

Thought this quote was interesting: "The southern United States is an inhospitable environment for the growing of exotic forest trees. The area has been compared with that of Siberia, without its severity, for its great fluctuations in winter temperature. This phenomenon prohibits the successful establishment of forest trees from most other parts of the world where the mean winter temperature can be even lower than that in the southern United States."

Also check this one out: "Eucalyptus: Gardening in the Coastal Southeast"

[PalmTreeDude]

Yikes! Does not sound like a good idea for me to plant one here! Thank you for the info! I will still be looking into this a bit more...

[PalmTreeDude]

This is the only site that I ever heard of that says one can be grown in VA. http://pubs.ext.vt.edu/3005/3005-1446/3005-1446.html 

[Matthew92]

This other site I found says Eucalyptus neglecta and dairympleana can take zone 7.

[Matthew92]

And check this one out too.

[Palm crazy]

All the ones mention above are really hardy and you might want to look into one which is not only hardy but very wind hardy. Eucalyptus pauciflora subs. debeuzevillei. It slower growing than most, but does really good here. 

 

 

 

 

[Steve Mac]

If you did get a snow gum (pauciflora) to grow there

 it would probably be too slow, as mentioned to serve you any purpose.

[monkeyranch]

Hardy Eucalyptus Page 

Australian National Herbarium site with advice for Eucs in cold northern hemisphere climates including species list.

And Windmill Outback Nursery in Louisa, Virginia which I first remembered when I saw your question.  Looks like their list hasn't been updated in awhile but worth an inquiry.

[Brian Bruning]

The South has many plants from the Asian mainland that have not only done well but have taken over.   Paulownia, Albizzia, Chinese Wisteria, Tallow Tree and Kudzu to name just a few have become weeds for you.   

Australia's climates are not at all similar.  They are mediterranean, desert, monsoonal savannah and their "temperate" east coast is more like LA with summer rain and as one goes north it gets progressively more tropical to a Carribean type climate.  Hot wet humid summers and occasional winter lows near -10C/0F are not what they get in Australia.  They are surrounded by the sea and there is no land mass to the south that would provide a polar front with temperatures much below -3C/25F until one gets to Antarctica.  

You'll do best if you stick with plants from northern India, China, Taiwan and southern Japan.  Some things from southern Brazil and northern Argentina will do well for you as they have a vaguely similar climate.  They do get some polar fronts that bring frosty weather but summer are hot, rainy and sticky.  The southern most three states of Brazil don't grow coffee for a good reason.   Every few years they get a hard frost and the trees are badly damaged or die.  So they stick with dairy, corn (maize), rice, soya beans, dry beans and things that don't need tropical weather.

The plants of the southern Brazilian highlands do well for me here in northern CA.   All I have to do is irrigate them in summer as we don't get rain from about May to about October.  They get an even rainfall pattern all year in southern Brazil.  But temperatures there at upper elevations are similar to mine and I can mimic habitat conditions. 

[VA Palmer]

I ordered five 'Big O' Eucalyptus Omeo Gum (neglecta) trees this past Spring from ToGoGarden/Gardener Direct for 7a in Northern VA.  They are in pots on the deck this summer (maybe two 1/2 feet tall) and I will keep them in the greenhouse through Winter.  I hope to plant them in Spring in my row around the pool area between my Windmill fortunei and Yucca recurvifolia.

[Chester B]

I hope you have a big yard - they get pretty big.  We have large ones around here and they are a great tree but expect 30-40' if they survive.

[Nj Palms]

On 8/4/2020 at 10:37 AM, VA Palmer said:

I ordered five 'Big O' Eucalyptus Omeo Gum (neglecta) trees this past Spring from ToGoGarden/Gardener Direct for 7a in Northern VA.  They are in pots on the deck this summer (maybe two 1/2 feet tall) and I will keep them in the greenhouse through Winter.  I hope to plant them in Spring in my row around the pool area between my Windmill fortunei and Yucca recurvifolia.

They will form medium sized trees in two years or more but a very strong vortex winter will knock them to the ground but they will resprout vigorously. I will have some neglecta, parvula,pauciflora, and stellulata for sale next spring. I will test their hardiness in multiple spots of my county in zone 7a New Jersey.

[Chester B]

Pauciflora is the hardiest Euc by far., but I'm too warm to really test them though.  I do have pauciflora, stellulata, perinniana, subcrenulata and neglecta and they all do well in my climate showing no damage even as seedlings.

[Nj Palms]

30 minutes ago, Chester B said:

Pauciflora is the hardiest Euc by far., but I'm too warm to really test them though.  I do have pauciflora, stellulata, perinniana, subcrenulata and neglecta and they all do well in my climate showing no damage even as seedlings.

E.Pauciflora ssp. Debuzivelli is hardiest but slow growing compared to others. E.neglecta and E.perriniana have done well I’m northern Virginia.

[Chester B]

1 hour ago, Nj Palms said:

E.Pauciflora ssp. Debuzivelli is hardiest but slow growing compared to others. E.neglecta and E.perriniana have done well I’m northern Virginia.

Depends on what you consider slow.  Stellulata so far has done nothing for me.  2 years from when I planted they aren't even 3' tall,  whereas Pauciflora will grow 4-5'/year.  I grow ssp "Niphophila".

Neglecta for me grows 5-6'/year and perriniana about 10'/year ( I want this one to stop)

[Nj Palms]

My Cinerea has put on 6 and a half feet so far. Have it in ground since last June as an experiment. My gunnii were starting to slow down from the heat but I gave them some fertilizer and they are rocketing up. If you have any perriniana seeds I’d love some if you like.

[Chester B]

On 8/7/2020 at 6:26 PM, Nj Palms said:

My Cinerea has put on 6 and a half feet so far. Have it in ground since last June as an experiment. My gunnii were starting to slow down from the heat but I gave them some fertilizer and they are rocketing up. If you have any perriniana seeds I’d love some if you like.

Don't fertilize them, they grow too fast as is.  They are from a continent with extremely poor soils.

My tree has been flowering for months, and I see hundreds of pods forming.  I can collect some but I'm not sure when they're ready to harvest?

 

[Nj Palms]

22 hours ago, Chester B said:

Don't fertilize them, they grow too fast as is.  They are from a continent with extremely poor soils.

My tree has been flowering for months, and I see hundreds of pods forming.  I can collect some but I'm not sure when they're ready to harvest?

 

I lightly fertilize since I want to maximize growth and establishment but they are going nuts despite the heat this summer. The pods will turn brown and you have to put them in a container to release seeds. Here is a good link.http://www.angelfire.com/bc/eucalyptus/seed.html

 

[Chester B]

When you fertilize you weaken them.  They grow too fast and can break, or can pull out of the soil because their root system is not big enough to support the weight of the tree.  Chances are yours will die back quite often so it may not be an issue.

[Nj Palms]

5 hours ago, Chester B said:

When you fertilize you weaken them.  They grow too fast and can break, or can pull out of the soil because their root system is not big enough to support the weight of the tree.  Chances are yours will die back quite often so it may not be an issue.

I wouldn’t fertilize my neglectas or pauciflora for that reason. The gunniis and Cinerea I don’t really care as I know they will most likely die back.

[tanyawales]

Eucalyptus neglecta (Omeo Gum) is cold hardy down to USDA Zone 7 at least. I grew two trees for four years in Boise, ID USDA Zone 6 and they grew five ft. in that time. I moved and the new owner of the house took out everything I planted, sadly.  :(

[Palm Man]

Eucalyptus neglecta is very hardy in Zone 7b of North Carolina. I have never seen it significantly damaged by cold. It is adapted to clay soils as well. 

 

[Swolte]

I heard the Neglecta do OK here in Central Texas but I haven't seen, nor heard, of much luck with other varieties/species. I wish I could grow a Pauciflora as these look amazing. I am trying a tiny Cinerea that I picked up at the Lowes (hoping it'll make me rich) but it has not taken off yet.

Any experience with eucalyptus in Texas? Plenty of poor soil here!!

EDIT:  This is what they claim on the page that monkeyrange shared (https://www.angelfire.com/bc/eucalyptus/selection.html). 
 

• The Southeast USA and Texas (referring especially to USDA zones 7 - 8) have very hot summers and mild winters with occasional hard freezes.  It is difficult to say what species will ultimately prove successful in this region, since it is too cold in winter for most of the heat-loving tropical and desert species, and too hot in summer for many of the hardy alpine species.  I would suggest that some of the best species for this region include E. aggregata, E. alaticaulis, E. camphora, E. cinerea, E. goniocalyx, E. mannifera and its subspecies, E. neglecta, E. nicholii, E. nortonii, E. nova-anglica, E. rodwayi, and E. stellulata; and possibly also E. bridgesiana, E. cephalocarpa, E. dives, E. morrisbyi, and E. tenuiramis.  There have also been local reports of some success with E. pauciflora ssp. niphophila in Alabama and Texas, and E. parvula and E. gunnii in Alabama.  Milder areas (zone 8b - 9) should do well with E. blakelyi, E. camaldulensis, E. microtheca, E. nandewarica, and E. polyanthemos.  Much more testing of eucs in the Southeast is needed.  (Milder areas of the Eastern Seaboard - eastern North Carolina, Virginia, etc. - might try some of the species recommended for the Southeast and for the Pacific Northwest, since the climate is not quite so hot as the Southeast.)

Edited February 7, 2021 by Swolte