Print

[acacian]

sorry! i meant to edit my post.. not quote  myself twice

[Endophyte]

Not all zones are similar, even when they have the same number.

A place that has a few nights a year that get below freezing can have the same official zone as a place that has those same freezing temps for 60+ days in a row each year.

Just because a plant is rated to a certain zone of hardiness does not mean it will actually survive in all areas in the zone.
I'm in zone 7 and there isn't any chance that an Acacia will survive outside here year round.

[AcaciaAve]

There's lots of different species and many are able to survive in extended periods of snow and freezing temperatures.
Species native to mainland Southeast Australia to Tasmania and that have naturalized in New Zealand have a good chance of growing for years in temperate climates. They can handle the cold but the big killer is usually strong winds toppling mature specimens or dripping cold rain weakening foliage on young plants.

The species that can withstand this the best are A. Boormanii, A. Dealbata, A. Decurrens, A. Mucronata, A. Pravissima, A. Rubida and occasionally A. Baileyana, A. Implexa, A. Melanoxylon and A. Spectabilis. Care and time must be invested to ensure they're able to grow in colder climates, it is very possible. Soil, planting location, and source of seeds is very important. Overwintering them in a greenhouse or indoors for a couple years will extend their lifespan greatly. Many are frost-tender when young but frost-hardy after they've developed a woody base and will resprout if they die back. There's a few other species which are less popular in cultivation such as A. Cardiophylla, A. Covenyi, A. Decora, A. Mabellae, A. Montana, A. Riceana, A. Schinoides, A. Terminalis, A. Tysonii, A. Verticillata and a few others which may handle the cold, rain, snow, freezing, some flooding etc. A. Acuminata Narrow Phyllode can handle the elements but also can be a slow-grower and is best to be overwintered in a greenhouse for a few years before planting outside. Surprisingly some thorn-Acacias such as A. Abyssinica, A. Caffra and A. Caven(Cavenia) may handle extended freezing periods, strong winds and some flooding. Most of the time you have to plant lots of seeds and a percentage of them will die but many may survive. Mulching under the canopy will also help preserve the trees and keep them alive much longer. Using frost cloth to cover young plants in the ground on freezing nights is also crucial for cultivating new species that haven't been tested in the region.

It is definitely worth a shot even down to Zone 6 for some species. Obtaining a small greenhouse is an excellent way to give your temperate grown wattles a better chance at living a long life.

[Endophyte]

I've been wanting to try some of the Tasmanian species from colder areas.