Botany The Acacia Grow Thread

[Wise_fool]

Any tips on overwintering acacia, zone 8b? SWIM is considering putting some seedlings heat mats set to a thermostat that will kick on around 35-40F. The idea isn't to heat the greenhouse really, just to keep it slightly above freezing. SWIM is also considering placing some milk jugs filled with water and painted black in between the plants, and wrapping their pots with bubble wrap. Could also mount a fan at the top of the greenhouse pointing downward to help circulate the warmer air that collects at the roof.
SWIM is also wondering about watering through the winter?

 

[acacian]

Hey @Wise_fool

Sounds very cold where you are! Which species of acacia are you growing?

My first suggestion would be to grow a known cold hardy species.. an obvious candidate would be Acacia phlebophylla - as it is from alpine environment that experiences long bouts of cold during winter. Other good options include Acacia floribunda, Acacia retinodes, Acacia acuminata, Acacia obtusifolia.. actually a lot of species have surprised me in the cold.

Insulating the pots is a good idea.. I’d maybe try and add another layer to your greenhouse. Keep your plants as high up as possible. The fan thing is a good idea. Alternatively you could keep them inside during winter in a sun room or something.. light won’t be as good but they should survive.

 

[Wise_fool]

Hey @Wise_fool

Sounds very cold where you are! Which species of acacia are you growing?

My first suggestion would be to grow a known cold hardy species.. an obvious candidate would be Acacia phlebophylla - as it is from alpine environment that experiences long bouts of cold during winter. Other good options include Acacia floribunda, Acacia retinodes, Acacia acuminata, Acacia obtusifolia.. actually a lot of species have surprised me in the cold.

Insulating the pots is a good idea.. I’d maybe try and add another layer to your greenhouse. Keep your plants as high up as possible. The fan thing is a good idea. Alternatively you could keep them inside during winter in a sun room or something.. light won’t be as good but they should survive.

Yes rather cold. Can reach -12 degrees Celsius. 10F. That is not very common but does happen.
What species? So far
Acacia acuminata ssp. longifolia
Acacia baileyana
Acacia floribunda
Acacia longifolia
Acacia mucronata ssp. longifolia
Acacia pravissima
Acacia prominens
Acacia oxycedrus
SWIM is interested in obtusifolia and phlebophylla but those have been hard to find. Also interested in other forms of floribunda, the wide phyllode variety with the weeping growth habit.
SWIM tried bringing plants in for the winter once with disastrous results, lost everything and not sure why. Hence the construction of a greenhouse.

 

[CheeseCat]

Curious if anyone has advice on promoting trunk growth more? The white willow floribunda in my garden seems to be producing boat loads of foliage but not gaining much height. So consequently some of the new growth is almost touching the ground. I know that spring is a time for producing foliage so maybe summer will be when it starts to pump out more height. Thoughts? Photo below..

My guy is kinda doing the opposite thing, focused on height more than foliage. I didn't quite get it all in frame, it's really reaching up, which might be because it's in part shade and not full sun, I'm not sure.

 

[acacian]

Wattles are going through a massive growth spurt at the moment. They must be loving the warm and sunny days after all the recent rain.. changed to a fabric material that lets them move more instead of having them tied to a stake with the plastic ties. It was digging into the stem.

 

[CheeseCat]

Gotta say your Obtusifolia has incredible looking phyllodes. Mine don't exhibit that much venation! Courtii is looking great too.

 

[acacian]

Gotta say your Obtusifolia has incredible looking phyllodes. Mine don't exhibit that much venation! Courtii is looking great too.

I'd be interested to see some photos of the veins on your obtuse? I remember when they were a fair bit younger the veins weren't quite as stunning. Could be an age thing or maybe is the variety you have? Do you know where the seed is from?

 

[CheeseCat]

Mine has some nice venation but it varies from phyllode to phyllode, some have a lot, some not so much. I think you're probably right though, likely an age thing. Your plant definitely looks a lot darker than mine. Will get back to you about the seed location, might be a bit tricky to find that one out.

 

[acacian]

@CheeseCat they’re looking absolutely beautiful! Nice thick stems already.. you must be happy. Yes that plant is quite dark.. my other obtuse (seed from south coast NSW) all look much lighter. I should probably take some photos of them as it’s been a while.

Great to see obtuse being grown.. I don’t hear people talk about growing it as often anymore.

 

[CheeseCat]

Cheers man, hope they keep thriving I'm a bit worried about some of my floribunda seedlings actually, the leaves look a bit pale to me and they look flat. Not sure if they need more light or nutrients? They're in a 50/50 mix of coarse river sand and standard seedling mix.... the courtii in the top lefthand corner also looks a bit unhappy. Funnily enough the ones that are going really well are in a screened cactus mix (darker mix on the left and top row)

Do these look ok to you?

 

[acacian]

They look ok.. Middle row second from the top looks like a 'runt' plant.. probably a bad seed. The ones with a slightly lighter colour is hard to tell.. they might be fine. I suspect is more to do with the seed itself than medium in the case of floribunda. That red colour is normal for courtii seedlings I'd say its not too much cause for concern just yet. Just keep a close eye on em all as I'm sure you know to anyways..

I'd ditch the seedling mix if I were you. Better to mix the river sand with something like peat moss or coir.

Much respect to you for growing the sacred wattles.

 

[CheeseCat]

Thanks for your help @acacian (always appreciated). Hopefully they are on the right track…

About the mix, won’t using only river sand and coir be pretty low in nutrients for the little guys? I don’t think coir has any nutrients. This has always confused me, how they’ll grow without soil…

Are all your wattles grown in this type of mix right up until you plant them in the ground? or do you start to add a native potting mix at some point?

 

[acacian]

Thanks for your help @acacian (always appreciated). Hopefully they are on the right track…

About the mix, won’t using only river sand and coir be pretty low in nutrients for the little guys? I don’t think coir has any nutrients. This has always confused me, how they’ll grow without soil…

Are all your wattles grown in this type of mix right up until you plant them in the ground? or do you start to add a native potting mix at some point?

A little fertilizer helps once in a while. But the early stages are really about letting that tap root develop. Yes all grown in the mix I mentioned.. with a little perlite. Occasional watering with seasol and sometimes scattering osmocote native fert on the surface.

 

[Brickwall_55]

Got these guy in an old plastic beer carboy, I did the cuttings on the weekend in 50:50 coir/sand and have been keeping them misted but wondering if i should be letting them dry out more? I have some in the garden in shade that dont seem as happy so guessing this might be the sweet spot.