Acacia Dormancy Question

[acacia_lover]

Hey folks,

I have a variety of acacia trees (fever, paperbark, tortilis etc). I live in the zone 8b and so bring them inside in the late fall and put them back outside in Spring.

I currently use grow lights in the winter on an 8 hour cycle. In the Summer they get up to 16 hours naturally outside.

The question I have is:

Should I continue to use grow lights or should I cut the lights and give them a few months of dormancy?

Cheers.

 

[Deep Sea Diver]

Greetings and welcome aboard Bonsai Nut! You will soon discover this is a great place to get good information about trees in pots.

Your question is Interesting. The simple answer is yes, keep lighting the tree. A tree doesn’t go dormant just because it doesn’t get light. However it will absolutely not like the change in routine.

The answer gets a bit more complex depending on the species and your location and if you are proposing keeping the tree outside all winter. The answer to that will vary if one is in Florida, Central America or Washington State.

Can you please enter your approximate location and USDA Cold hardiness zone. This way we can properly answer this and future questions. To do this, click on your icon, then account details, then scroll down and enter the appropriate information.

Best Wishes
DSD sends

 

[dbonsaiw]

I would continue with the grow lights as these are generally tropical and subtropical and I do not believe they go dormant as far as I know. I have some vachelia (a cousin of acacia) and keep them under lights indoors all winter here in NY.

I have the lights on for about 13 hours/day. Not sure if that's appropriate or not, just what I am doing. Trees seem to like it so far.

 

[rockm]

I think this may depend on what kind of acacia you're talking about. Dormancy in the arid subtropical environments some are from is driven by moisture, not temperature. Dry season--dormant, wet season, growth. Those don't necessarily coincide with northern latitude winter and spring.

 

[fredman]

Hey folks,

I have a variety of acacia trees (fever, paperbark, tortilis etc). I live in the zone 8b and so bring them inside in the late fall and put them back outside in Spring.

I currently use grow lights in the winter on an 8 hour cycle. In the Summer they get up to 16 hours naturally outside.

The question I have is:

Should I continue to use grow lights or should I cut the lights and give them a few months of dormancy?

Cheers.

I live in zone 8 and leave my Acasias outside all year. They are cold hardy as long as it dont freeze to often.

 

[Russ1]

It depends on how much light they get and it's most likely a lot less than if they were outside.
I keep my BRTs under lights, about 13000 Lumens for 14 hrs a day in the winter inside.
While they don't really go dormant they will have a rest period which I don't think you have to force.

 

[acacia_lover]

I would continue with the grow lights as these are generally tropical and subtropical and I do not believe they go dormant as far as I know. I have some vachelia (a cousin of acacia) and keep them under lights indoors all winter here in NY.

I have the lights on for about 13 hours/day. Not sure if that's appropriate or not, just what I am doing. Trees seem to like it so far.

Thanks for the input. I've always kept them inside under lights in the Winter and while they don't go dormant, growth certainly slows down. Nigel Saunders has a video showing acacias going without lights for the winter and they went dormant. They came back in the Spring which made me wonder if I should adjust my strategy.

 

[acacia_lover]

I would continue with the grow lights as these are generally tropical and subtropical and I do not believe they go dormant as far as I know. I have some vachelia (a cousin of acacia) and keep them under lights indoors all winter here in NY.

I have the lights on for about 13 hours/day. Not sure if that's appropriate or not, just what I am doing. Trees seem to like

I appreciate the input. Do they grow in the Winter under those conditions? When do you prune yours?

 

[acacia_lover]

It depends on how much light they get and it's most likely a lot less than if they were outside.
I keep my BRTs under lights, about 13000 Lumens for 14 hrs a day in the winter inside.
While they don't really go dormant they will have a rest period which I don't think you have to force.

They are getting far more light inside as the days are very short here in Winter. I don't get leaf drop but growth slows down a fair bit. That's the question, do I need to force full scale dormancy as to not impair their Spring growth.

 

[acacia_lover]

I live in zone 8 and leave my Acasias outside all year. They are cold hardy as long as it dont freeze to often.

 

[acacia_lover]

That's interesting. I assume that they drop all their leaves?

 

[Russ1]

They are getting far more light inside as the days are very short here in Winter. I don't get leaf drop but growth slows down a fair bit. That's the question, do I need to force full scale dormancy as to not impair their Spring growth.

Yes, getting more light inside now but less than when outside in summer, plus far less UV light if any.
Plants sense small changes in light, temp, humidity and react accordingly. My BRTs slow down in Dec, Jan and Feb, then start growing again in March without me doing anything and they have tons of light. Day Length here now is only 9 hours.

 

[dbonsaiw]

Dormancy in the arid subtropical environments some are from is driven by moisture, not temperature.

How does this type of dormancy compare to the dormancy of deciduous trees? Specifically, do sub-tropical trees require dormancy in the same sense as deciduous trees do and will weaken/die without dormancy?

 

[Mikecheck123]

I have a Bailey Acacia and a couple of Oven's wattles (acacia pravissima).

The Bailey Acacia is really easy and doesn't mind being a house plant for 6 months a year. It will absolutely not survive below 25F, though. I learned the hard way! My first winter in Virginia, it died back to the ground, but started growing again once I brought it inside.

The acacia pravissima i have much less experience with. One of them just dropped all its leaves. I put it in a warmer and sunnier spot than it was, and am crossing my fingers. I don't use grow lights at all.

 

[rockm]

How does this type of dormancy compare to the dormancy of deciduous trees? Specifically, do sub-tropical trees require dormancy in the same sense as deciduous trees do and will weaken/die without dormancy?

i don't really know. I have heard that this kind of dormancy is resource specific. Shutting down in dry periods makes sense, just like shutting down in freezing cold/darker periods does for trees. It would be a waste of resources trying to grow during those kind of times...BUT if water returns, that changes, just like lengthening daylight.

However, I don't know if a tree in a drought-induced dormancy would die if deprived of it since the resource driving it (water) is relatively unpredictable compared to the clockwork of day length periods.