arisaema seeds

[MarcR]

Véronique,

It has a similar effect to Gibberellic acid.  I'm not sure of the chenistry; but, I think it stimulates the prodoction of  auxins [growth hormones] in the seed.

[Jeffnz]

A very scientific article on the topic.
https://www.mdpi.com/2674-1024/1/1/2#:~:text=Potassium%20nitrate%20(KNO3)%20has%20been%20demonstrated%20to%20break%20seed,10%2C11%2C12%5D.

[Véronique Macrelle]

Thanks Jeff,
it's interesting, and I'll certainly give it a try if I find some Arisaema seeds to sow.
Perhaps you could put this link on the Arisaema sowing thread too?

[Véronique Macrelle]

it's interesting, and I'll certainly give it a try if I find some Arisaema seeds to sow.

Have you already tried it?

I tested some Ga3 on A. tortuosum seeds one year. Not only did they germinate well, but they also grew very vigorously, with a second stem/leaf on each bulb.
They flowered after the 3rd spring.
 but no action on thunbergii, griffithi or sikkokianum... sown several times. but i've since read that you need seeds stored moist...

[MarcR]

Véronique,

I don't grow many Arisaema seeds; but, I have used it successfully on many other difficult seeds.

[Véronique Macrelle]

I finally bought/ordered the seeds of 5 species of Arisaema, 10 seeds/package which were harvested in 2023, but the seller certifies that they will germinate well: concinnum, costatum ,formosanum, ringens, urashima.

for urashima, which is said to be Arisaema thumberghii var urashima, it would be in my interest to sow it as soon as I receive it? (maybe in 2 weeks)
 Does it germinate hypogeously in the first warm season?

[Vinny 123]

If you search enough of the www, KNO3 is mentioned frequently, but the soaking period used varies hugely.

I found one paper recently (I do not recall the species concerned), and their experiments looked at three different concentrations and the lowest gave the highest/quickest germination, but they did not do the obvious and look at a still lower concentration.

Probably the commonest concentration recommended is 1%.

I have tried with a few seeds but not enough to make any useful comment about concentration/soak time. I have two Androcymbium (now Colchicum) seeds that have germinated, which is not many, but approaching 100% more than most people see, me included with un-treated seed. I am hoping for more as the weather cools.

I make 10ml (1%) at a time, in a small (~7cm diameter), shallow dish and use a tea-strainer (very fine stainless steel seive) to hold the seeds - it makes life very easy that way. I also do not rinse after soaking, I just drain them on kitchen towel, still in the strainer, sow and then mist them to settle them into the compost, usually top-dressed with 2-3mm of very fine grrit.

[MarcR]

Véronique,

My method is very similar to Vinny123's.  I use 1/4 tsp per 0.5 liter of water [1/8 tsp per cupful].  I soak the seeds in a cupful of solution for 3 hrs and pour the solution through a coffee filter in a funnel to recover the seeds.  This works well even for very small seeds.  Several Violas, that are difficult to germinate, respond well to this treatment

[Véronique Macrelle]

thank you for all this information. it's really interesting!

[Véronique Macrelle]

I'm disappointed to find very few Arisaema species in the SRGC list this year, compared with other years!
So I won't have anything new this year, whereas in previous years there were costatum, heterophyllum, urashima, triphyllum, serratum... and sometimes others...
I have the impression that finding different Arisaema is now becoming almost impossible and that I'll have to accept it.


I've also realised that I have to keep a close eye on all the plants (in all families) and pollinate them by hand now. What an impossible job!


I was surprised to find plants in the garden that used to fruit systematically and are now seedless, such as Digitalis and Verbascum. As a result, Digitalis lanata and ferruginea have disappeared from the garden, even though they were plants that renewed themselves.
Gooseberry bushes that no longer bear fruit, etc. other fruit trees that do so very little.


 The phenomenon is becoming more and more obvious: here, there aren't enough insects to do the job any more, which is very sad... :'(

[Tomte]

I'm disappointed to find very few Arisaema species in the SRGC list this year, compared with other years!

Veronique, I believe the seed list on the SRGC page ist still last year’s list. The new list will appear sometime soon, as it still needs to be compiled, with the deadline for donations being only tomorrow. So, all is not lost yet 😉
BR,
Tom

[Véronique Macrelle]

The list hasn't been finalised yet? so I'm still hopeful!

[Robert]

Véronique,

Your disappointment and frustration are understandable. Maintaining genetically diverse, yet pure (true to variety or species), seed lines is a great deal of work and takes a degree of skill and accurate knowledge. Excessively inbred seed lines that lack genetic diversity and unintended hybrids abound.

I get many complaints that the diversity of species available for garden use is declining. Maintaining lesser-known species in cultivation has been an ongoing problem for years – read Seeds of Adventure for some examples. Climatic change is only compounding these problems. Fortunately, there are methods that can greatly ameliorate these issues, however as you know, one person cannot possibly maintain hundreds of seed lines. Here in the U.S.A. the U.S. Department of Agriculture maintains a large seed bank with thousands of species and varieties. It takes a large trained staff to maintain the seed lines and only a small fraction can be grown out each season.

May you have good luck with you endeavor. Keep in mind that excessively inbred out-breeding species can lack vigor or suffer from inbred depression. They also might be masquerading as true species but are unintended hybrids. In addition, continually selfing inbreeding species is a very poor strategy for maintaining a species or variety. For example, this is a common practice for those that maintain large collections of tomato varieties. Continually selfing one plant of each variety generation after generation works, sort of, however these excessively selfed varieties lack the genetic diversity they once had and can be very susceptible to adverse growing conditions and be lost to cultivation. In their natural habitat, inbreeding species out breed more than we might want to believe. Science has demonstrated this repeatedly.

[Véronique Macrelle]

It's also why I like to get several individuals per species, and why I like sowing... I like to see a bit of diversity...
but the question is: what will happen to a world without insects?

[Vinny 123]

Certasinly in the UK, insect numbers were massively down this year - very cool and very wet until late spring, a cool summer with plenty more wet weather - the only invertebrates to do well were molluscs.

A Cottoneaster and the Buddleja here would normally be smothered in insects when in flower, but they were very few and far between. The only mass of insects that I have seen all year was last week - a large clump of ivy in full flower, in very warm sunshine, facing south - it was humming with numerous species of fly.

If we get a mild winter and an early and warm spring next yearr, people will be cursing about bugs at picnics just the same as ever.

The prophets of doom in the UK use a year something like 20-30 years ago as their "standard" and compare insect counts to that. The problem is that that year is now recognised as a year of super-abundance of insects.