Guide to Boswellia sacra (Frankincense) germination

[Marcel]

A while ago there was some discussion on this forum (and AE as well) about Frankincense (Boswellia sacra) seeds and germination. If you're lucky enough to find the seeds, you're then blessed with the fact that they have horribly low germination rates. Internet lore seems to say 1-2%! There's also the widespread belief that they are only viable for a few weeks. I must say, being somewhat of a newb at gardening, these facts turned me off a whole lot.

Then, out of nowhere, our own WoodDragon contacted me asking if I wanted in on a whole bunch of seeds from a reputable source. This source said that they have 8-10% success and that they've found this rate to be consistent with 5 year old seeds. I said "What the hell? Why not?!" and a few weeks later I had a packet of 100 Boswellia sacra seed. Woodie bought "Cultivation of Boswellia: Sacred Trees of Frankincense" by Jason Eslamieh and graciously transcribed some of the seed germination info for me. With the help of this book and WoodDragon's Australia specific interpretations, I came up with a good soil mix and germination method.

WoodDragon: Thanks heaps, buddy. You're a good guy.

Anyway. Here we go.

Here are the notes from WoodDragon:

The germination mix is:

- 20% organic (Eslamieh recommends a sterilised (commercial?) mulch without water crystals or fertiliser)

- 80% well-draining mix of equal parts of:

1) 'solid' material such as 5-10 mm pumice (good luck finding that!), expanded clay balls (the local hydro will have Hydroton or similar), or decomposed granite (local landscaping centre)

2) perlite (nursery or hydro)

I'm gambling and playing with my own mix. I'll be using about 10% crushed/dusted limestone, 10% crushed/decomposed granite, 20% expanded clay balls, 20% perlite, 20% arena/propagating sand, and 20% premium mulch or seedling coir. At least, I'll see what it's like - I might vary until it feels 'right'!

A few notes:

- The limestone and granite are sieved/washed to remove most of the fines/dust, and pebbles bigger than about 15 mm.

- Eslamieh says that peat can be used as the organic phase, but that a mix with it has to be changed once a year in case it starts to rot.

The seeds are sown into this, top-dressed with 5-6 mm screened pumice (I'm going to use a layer of perlite), and "watered thoroughly". I am going to soak the seeds first for an hour in tepid rainwater, and then sow, water, and drain well for an hour or so...

Eslamieh says incubate at 27 C, and at 80% humidity...

Eslamieh uses a 150-200 mm plastic "bulb" pot for 100 seeds, which seems crowded but he has a picture proving it. It works for B. sacra because of the poor germination rate...

Apparently is takes a few days to a few weeks for germination. After this, the big thing is lots of sunlight or good artificial light. Remove the cover after germination so that humidity decreases, and avoid water directly on the seedlings. Allow the mix to become almost dry (about a week, apparently) before watering again, and water from the sides so that the seedlings' leaves aren't soaked...

After a year they are potted up, with the same mix but with 30-50% organics.

Based on this I used some of my favourite coarse sand mix: Nepean River Sand.

This stuff is dusty, so I washed it carefully.

I got myself a 20cm plastic pot and trimmed it to make it shallower.

Then I got some good bulk organic veggie garden soil mix. It has no ferts or water-retention agents in it. It's also quite sandy, as you can see here.

I mixed the Nepean River Sand mix with perlite at a ratio of about 50/50, and added the soil mix (from which I discarded the bigger sticks and rough bits). The final mix was about 20% soil mix, 40% perlite and 40% river sand.

Here are the seeds. They're diamond-shaped and quite papery and not quite as red as they appear in this photo. They're about ~3mm long.

I placed the pot with seeds sprinkled evenly on top, covered in a light layer of perlite, on top of my DIY heat mat (100W aquarium heater siliconed into a hole in the side of a large cake tupperware box). The pot is in front of a large north facing window with opened shutters stopping direct sunlight. The temperature has been fluctuating between 22 degrees in the night and 32 degrees during the day.

I covered the whole pot with a DIY dome with humidity regulated with foil over the top opening. I misted lightly every 3 days.

Six days later (today) I awoke to one of these.

Throughout the day, 2 more of these guys showed some sort of life.

It's early days still, I know, but I thought I'd throw this up and keep you all informed as they progress. Hope the rest of you attempting this fickle beast get something out of these notes.

[WoodDragon]

I'll have to trawl back through my emails, but these seeds are from early 2010 if I recall, or perhaps late 2009. So my source was definitely right about the viability, confirming my original suspicions - that the germination issue with B. sacra has more to do with the inherent viability of the seeds produced, than with their age. As I have said elsewhere, the low rates of germination are probably an inherent aspect of the species, perhaps caused by or aggravated by its current genetic diversity. Either way, the important thing is not so much to get the very freshest seed possible, but rather, to get a decent number of seeds that have been stored properly... and then to provide the appropriate germination conditions.

Of course, having said that, fresher is always better - try growing bamboo by seed for instance!

Anyway, I had better get my act together and set my own seeds up. I've been holding off partly because temperature and light are issues in our winters here (adequate light is critical for seedling growth), and partly because I am busy with new enterprises. Still, I know that Boswellia can successfully grow down here, as I met one a just few weeks ago, quite a few years old smelling as divine as I had always imagined. And it was a very neglected one indeed, so the buggers are tougher than many people suspect.

Ah, Boswellia...

[tripsis]

Six days?! Hell, I should have got some seed! Great work Marcel, very jealous.

[planthelper]

very jealous aswell!

nice writte up, great pics, this will certainly inspire a few of us, to try the same.

i use aswell at times, "shortend pots", i think they are better because, as you can see, you can better "dome" them and aswell, they store far more soil than punnets, so you don't have to worry about "an early, maybe root harming repot".

can't wait, to see more pictures of your project! <___base_url___>/uploads/emoticons/default_wub.png

[Marcel]

Thanks for the support, guys. Now that I have 3 germinated seeds, I'm thinking of taking the humidity dome off and putting it in some light. Woodie: you reckon Eslamieh means direct light? I've got the pot in a north facing window, but out of the direct hit of the midday sun... I find talk of light confusing in horticulture. I wish people measured it in terms of lux or candles/square inch and colour temperature (that's my past as a photographer talking).

[WoodDragon]

Bright indirect light at first, but they should probably be able to handle anything but direct mid-day light almost straight away, especially if it's not summer.

Just keep an eye on them. If they start to etiolate give them more light immediately. If they start to curl or otherwise look like they're burning off, shade them from the most intense light.

Now that they're germinating you can certainly decrease the humidity. I'd do it in stages though over a day or so, so that you don't risk shocking them. Just put increasing numbers of holes in your plastic, until it's like a collander and not holding much humidity in. Doing it slowly will also give some of the remainding seeds just a little more time to take up moisture and germinate.

It's important not to over-water them now, or wet the leaves directly. Keep the day warmth up to them, and don't worry about the cooler nights, as that probably mimics the desert nights anyway.

Tripsis, I might yet arrange for another batch of seeds, depending on how many I get up. If so, I'll let you know when I do so. If you're patient though you can just wait until our seedlings are bigger, as frankincence is supposedly ridiculously easy to strike from cuttings.

Edited August 12, 2011 by WoodDragon

[Marcel]

Well, it's about 5 days since germination. I've slowly decreased humidity. I've given them plenty of indirect light. And I can't seem to find one of the germinated seeds. The other two haven't really budged at all. Still just seeds with a tail (this is called the radicle, yeah?). I'll give them some indirect water today, maybe... Temps are still reasonably high...

I'm nervous.

[planthelper]

what to you mean, can't find the seeds?

in case they have dissapeared totaly, they must have damped off, or nicked by an insect or rodent.

but i think your set up is safe, against the last one.

so what happend? if they are damped off, than you have to change your set up.

i would not be surprised if a desert plant would die if it's born into high humidety and no air movement.

in case they have damped off, just sow them out in the open next time arround, this often fixes damping off issues.

[Marcel]

No, they haven't succumbed to dampening off. I had three seeds germinate and now I can only see two of them. They're tiny and in among a layer of perlite, so it's tricky to see. But the two that I can see still look ok, it's just that they don't seem to be developing at all. Perhaps they're just sending down a hefty tap root before they throw out their cotyledons.

But I don't think it's too damp for them. If anything, it's probably too dry.

[Marcel]

Well, I might as well add the post script to this sad little saga.

The B. sacra seedlings are dead. They died about a week and a half after they germinated. I'm no expert, but I think that the emphasis to keep them dry and avoid rot is either overstated, or I overplayed it. They simply dried out and died, I think.

Anyone else trying these seeds: perhaps keep the humidity dome on a little longer than the above instructions suggest. Especially if using a heat mat and a warm north facing window sill (though I did keep them out of direct sun). And good luck!

[Auxin]

Well I'm giving it a go now. My seeds were sourced from Sacred Succulents.

Just surface-planted 31 seeds in a mix of 1 part potting soil, 2 parts pavers sand, 2 parts perlite.

Then for the next 31 seeds I took 2 parts of that previous mix and added 1 part limestone (particle size ranged from sand to small gravel size, with some powder in).

I misted them with distilled water and put petri dishes over the tops of the pots and little saucers under and placed the whole conglomeration on top of a thin board on top of a 1 cm thick metal sheet on top of a plant light to maintain temps from a night time low of 19° C to a daytime high of 31° C. They have a bit of light due to a nearby plant light 40 cm higher up. 16 hour photoperiod.

I'll post some porno shots if I get seedlings <___base_url___>/uploads/emoticons/default_smile.png

[Sallubrious]

I've never grown Frankincense, but I've moved away from all these sterile seed raising methods. I found it causes more problems than it is worth. If the growing medium is sterile it's just easy prey for the first organism that comes along. In my experience the first organisms that move in are often pathogenic and cause a lot of damping off and mould issues.

My seed raising mixes are based on sterile ingredients but I always add a healthy culture of microbes in the form of worm castings or give them their first watering with water that has had worm castings dissolved into it. For larger seeds (not the case here) I soak them in a mix of worm castings and dechlorinated water and that really gives the seeds a good head start.

These days I also inoculate with Trichoderma and now all my damping off issues are a thing of the past. The Trichoderma gives the plants protection from pathogenic fungii .

I can see sterile culture has its place but often the seeds themselves are carrying mould or spores that has come from mould which is very common on most mature seed pods. In nature that mould is not an issue but it doesn't take much to ruin a new seedling without the natural competitor fungi and bacteria in a sterile culture. Anyone who has grown mushrooms will know of the multitude of opportunistic organisms busting their arse to colonise any sterile culture and what a battle it can be to keep them at bay, my philosophy is to beat them to punch with a known healthy culture.

If I was going to use a sterile medium I'd say it was pointless unless the seeds themselves have been sterilised or treated with a fungicide.

[planthelper]

i like your post a lot, and there are many different paths, all leading to rome.

what realy counts is the endresult, i'm sure worm castings and composts contain bacteria which aid plant growth and root formation.

but one has to have some experience with what one is doing, like with all things in life.

my wormcastings quite often contain gnat larvae so, it's out of the question for me to add this to probagation mixes.

auxins, attempt is taking place in the middle of his winter, in case you haven't noticed!

i love those, indoor garden projects, when ever i'm in temperate climats, because the artifical light setup, becomes a place of refuge.

Edited January 1, 2012 by planthelper

[Distracted]

SallyD

I've had a friend keep recommending me to use Trichoderma in my soil mixtures or create a Trichoderma LC to pour onto my plants but i've been extremely hesitant to mess with that nasty green mould for fear it will contaminate my house and ruin all future mushroom projects. Do you think i'm being overly paranoid?

Good luck auxin!

[Sallubrious]

SallyD

I've had a friend keep recommending me to use Trichoderma in my soil mixtures or create a Trichoderma LC to pour onto my plants but i've been extremely hesitant to mess with that nasty green mould for fear it will contaminate my house and ruin all future mushroom projects. Do you think i'm being overly paranoid?

Good luck auxin!

 

If you have mushroom projects going I'd say the Trichoderma may not be suitable for you. Trichoderma is like any other mould or fungus and is capable of producing an enormous load of spores under the right conditions.

I've successfully grown mushrooms in a damp house with a fucked roof that was absolutely infested with Trich. though. All my bulk subs had to spawned outdoors and covered up well before bringing them inside, once colonised they were very resistant to any contamination.

Chances are your house will have some Trich present anyway but if I were still growing mushrooms I'd avoid that green bitch like the plague.

For plants though the difference between a plant inoculated with Trich and one that isn't is very noticeable, I won't grow anything without it these days.

[Marcel]

That's fascinating, Sally. Thanks for sharing!

How did you get your Trich culture? Are you sure it's Trichoderma? There are a lot of look alikes..

[Sallubrious]

That's fascinating, Sally. Thanks for sharing!

How did you get your Trich culture? Are you sure it's Trichoderma? There are a lot of look alikes..

 

My first (assumed, I never examined it microscopically) Trich culture was obtained from a damp spot in my yard where it was growing on an old fence, everything in that part of the yard was super healthy so I took a punt and cultured it in a aerated liquid culture (A 20 litre drum with a fish tank air stone) I used pulped paper and molasses as a nutrient source. I started inoculating select plants with it and everything I put it on grew really well so I put it every where

When I moved house none of my newer plants were doing very well and I didn't have access to the (assumed) Trich from the old house so I looked around and found a local product that has a blend of mycorrhizal fungi and Trichoderma in powdered form. I couldn't find any details on what particular strain of Trich it contains.

I was trying to source a hybrid strain (T harzianum or T-22) but had no luck so now I'm using one named Nutri-life Platform.

http://www.nutri-tec...e-platform.html

Since I've been using that things have really picked up

From the website of Cornell University

Pathogens controlled

So far as the author is aware, different strains of Trichoderma control every pathogenic fungus for which control has been sought. However, most Trichoderma strains are more efficient for control of some pathogens than others, and may be largely ineffective against some fungi. The recent discovery in several labs that some strains induce plants to "turn on" their native defense mechanisms offers the likelihood that these strains also will control pathogens other than fungi.

 

http://www.biocontro...richoderma.html

[Auxin]

Well it was worth a shot.

The limestone mix yielded two sporuts at days 8 and 9 (making for a 3% germination rate overall and 6% from just the limestone group, better than the oft quoted 1% germination standard)

Unfortunately on day 17 they both died with their seed coats still on

At least I got some Trich. hybrids out of the same seed order, lol

Edited January 17, 2012 by Auxin

[klip247]

Just the thread I was looking for, anyone else get past the two weeks? I have two sacra's that are doing quite well, a few of my other ones are starting to wilt and dry up, this might possibly be a humidity issue, the germination rate isn't great, but I've had worse with other types:

[planthelper]

congratulations klip, many tried and it looks like you cracked it! <___base_url___>/uploads/emoticons/default_worship.gif

they look very cute, i wish you all the best with them for the future.

and, what a thread this one is, seems like the sab crew never gives up,

aaaaaaaaawesome! <___base_url___>/uploads/emoticons/default_wub.png

[Java Lee]

Hi , my friends

I like Boswellia very much ,

but I think Boswellia sacra is difficult to plant.

[klip247]

Nice Java, I had about three or four which I decided to plant out.... they didn't make it. I will have to try again, but this time I will be more careful where I place them.

Edited April 3, 2014 by klip247

[endorfinder]

I have some seeds on the way from a vendor a few people here have had success with. If I was to sow them in tropical NQ what would be an appropriate time, as we cool off a little and dry off a little, although it's still raining at least once a week? And what about in more temperate climates?

To those who've sowed seed with dismal germination rate - how many seeds do you use per how many of what type of pot without driving yourself crazy trying to keep soil moisture within an appropriate range?

[incognito]

This will be my project next spring. The boswellias are well suited to my climate.

[MountainGoat]

At six months... A few hiccups along the way but looking pretty good now...