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[Frog Pajamas]

Hi, I've been trying to get some Acacia seeds started over the past 10 days, with so-so success. I started Acuminatas and Maideniis as the same time using the same treatment. The Acuminatas germinated and have now started to sprout above the soil, but I've only gotten one Maidenii to germinate. I didn't scarify any of the seeds for fear of killing the embryo, and instead hot water soaked for a few hours, left to continue to soak without maintaining heat for 24 hours, and then transferred to damp paper towels in a sealed container. I re-heat soaked and soaked those that didn't swell and germinate after the first go, after they had been in paper towels several days, which got the last acuminates going but not any more maideniis. Any suggestions to get these little guys going?

[Greentoe]

Might be worth it to try scarifying them. I recently tried starting some mimosa opthalmocentra seeds. I had just soaked them in warm water for 24 hours. I had figured that'd probably do the trick since it worked for some other mimosas and acacias I've started. None of them popped up. So I think it was three or four days ago now I dug them up and scratched them up a little with a metal file. Since then four of them have popped. If try just filing them down until you get through the seed coat.

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[Frog Pajamas]

I will give it a go. Thanks for the reply.

[olyd88]

Nice, i've been trying to germinate some of maidenii seeds few weeks ago but no one sprouted, what i did is nicking the seed coat just like m.hostilis seeds method and hot water soak but it just molded and nothing happen. I hope i'd be able to germinate some of the seeds soon.

[Mandrake]

The scarifying/soaking routine should work fine for most acacias. But after the soaking (that is, once the seeds are at least a little swollen) there may be problems in case of species that take longer to germinate, particularly when sowed in organic substrate. Molds and even otherwise beneficial fungi can slowly take over the seed and keep it from sprouting. I have seen this happening even using plain coco coir without compost - otherwise viable and swollen seeds became crowded with mycorrhizae before they had a chance to peek.

In cases like A. Maidenii or others that can take up to a month to sprout, I'd approach it like this:

1) Scarification is optional, but well performed it won't hurt - most research agrees it increases germination rates in many mimosoids.
2) Take water to boiling point. Remove from stove, pour in a little container with the seeds.
3) Allow to cool off overnight.
4) Pick carefully the swollen seeds and place them inside of a sterile ziplock bag between moist, clean paper towels. Keep the ones not swollen for another day soaking, discard any seeds still floating.
5) Check ziplock bag every couple days or so, and sow 5-10mm deep in soil those showing the germinal root visibly.

Kind regards,

Mandrake

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[happyconcacti]

I pretty much do what Mandrake outlined above, but without the paper towel part:

1) gently nick pointed end of seed until inside, white part visible
2) boil water and allow to cool until no bubbles, steam still present.
3) place seeds in a cup, add hot water
3.5) place on seedling heating mat
4) leave overnight, sometimes longer
5) sow seeds in 10:1:1 of potting soil : perlite: vermiculite
6) place in propagation chamber or humidity dome

Here are some notes I took on 22-2-13 (d/m/y) using the method described above. They're not complete but its what I have.

The prior procedure, steps 1-3.5, done on various species:

1) A. Maidenii
2) A. Acuminata var. Narrow phyllode
3) A. Simplix
4) A. Burkei
5) M. Hostilis (jeruma)
6) D. Illionensus

At time = to 1 hour on seedling mat:
1) A. maidenii--swelling apparent from nicked end, outer coating showing cracks forming
2) A. Acuminata var. Narrow phyllode-- swelling apparent, looks like needs more time
3) A. Simplix-- very little swelling, slightly lighter in color
4) A. Burkei--outer coating peeling off, inner part of seed very swollen, does not look good
5) M. Hostilis--swelling apparent from nicked end
6) D. I. -- swelling apparent, seed coat separating off

At time = 24 hours:
1) A. maideni.--showing small white point where nicked, fully swollen
2) A. Acuminata var. Narrow phyllode--same as before
3) A. Simplix-- slightly swollen, needs more time?
4) A. Burkei--outer coating completely fallen off, looks bad
5) M. Hostilis--already showing small tap roots, fully swollen
6) d.I.--same as mimosa hostilis

Results:
The simplix and Burkei never germinated. All the rest were sown, germinated, and are alive and very happy.

Also, with mimosa verrucosa, the same thing happened as with A. Burkei. Maybe the seed coatings are too thin to withstand this method of scarification and soaking. Perhaps the paper towel method is better for these two. I do not know.

Hcc

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[Greentoe]

The simplix and Burkei never germinated. All the rest were sown, germinated, and are alive and very happy.

That's interesting. I ended up with a 90% germ rate on acacia simplex by just poring near boiling water on them and letting them soak for 24 hours. Most of them popped up within the first week or two. A few stragglers didn't pop until about a month later, but on the whole I had a pretty high germ rate with them.

I wander if maybe the ones you had weren't as fresh or something.

Can't really say too much about maidenii because I haven't grown it yet, but hopefully I'll be giving it a try sometime soon.

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[Frog Pajamas]

Thanks for all the replies.

They are all swollen at this point, so I'll just wait them out instead of scarifying. It sounds like I may just need to give them a little more time. Maybe I'll put half in soil and keep half in the paper towels to see if there is a noticible difference in time/germ rate?

I can report that the one Maidenii that germinated (planted in soil after the germinal root sprouted) has now sprouted above the soil, so that's good. All the Acuminatas have their first set of tiny leaves, so that is also exciting.

Now I just have to figure out what to do with my clothes as my closet garden keeps growing:P.

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[mr.miyagi]

I had to most certainly scarify my A.simplex seeds, and let them soak for a number of hours, I maintained a temperature of about 80 degrees in the water, And only one successfully germinated, I have another batch going wich are beginning to come to life.

[Hummingbird]

What I did was simply rubbing the seeds with sand paper until it was slightly "scarified". A. Maidenii and A. Acuminata had great germination rate, Obtusifolias not so good. Might be due to seed viability. It was years ago, but I'm pretty sure I did no hot water treatment, sand paper and paper towel method worked great for me.

[xoma]

I placed the seeds in a cotton bag lit a magic wand a exhaled in it for some minutes put them in a glassbowl added some ash and poured the boiling water over them and let soak over night. Most of them should have expanded and are ready to plant in the soil. Repeat the boiling water step with the ones that stayed the original sized in the first round.
Has worked grate for me.

Cheerio Xoma

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[LoveAndTrust]

Very informative post guys! I'd never heard of scarifed seeds before, lol. Hopefully I'll have time to do some scarify and nicking trials with my few species of acacia seeds. I'll try to make it as scientific and documented as possible. XD

[Frog Pajamas]

Ime, the key with the hard coat seeds (mimosa and acacia) is getting them to swell before planting them. Sometimes it takes a couple hot water soaks or a few days of messing with them, but if you get them to swell they'll likely germ and grow.

[Mangrove]

why not try microwaving a few of them whilst immersed in water? Its worth a shot; idk what will happen to them but I would love to find out.

[nikshaz]

Maidenii was by far the hardest for me,
I went through 20 seeds and got two plants to successfully grow.
Swelling the seed in hot water then sowed, it took about 2 weeks for a sprout, at least IME.