crocus seed germination

[maryam]

Hello
I got some crocus seeds. How should I keep it?
And how should I plant it? What soil can I use and  what temperature?

[mannextdoor]

Hello members,

I know, this is reactivating an old thread but I also want to ask this question. How should I sow the crocus seeds (spring and autumn flowering species)? I would say I am a experienced gardener (germination/cultivation  of Mandragora, Przewalskia, mediterranean Colchicum, ...) - no problem. Seeds from crocus growing in my garden (around 20 species) germinate themselve in my beds. BUT, I ordered a few seeds from the last seed exchange (2021) and I had a zero germination :-(. Any hints for germinating the seeds from the exchange? I handled them as recommended on the internet: soaking for 24 hours in plain water, sowing in a gritty, sandy substrate, allowing the nature do her thing (outdoors, also over the winter). Can someone help me with some hints or methods for a good germination rate? Or should I be more patient and the seeds will germinate in autumn this year or next spring?

Thanks in advance!

Greetings
marcel

p.s.: I forgot, Iīm located in middle Germany (just to got some idea about the climate).

[tonyg]

Hello Marcel
It sounds to me as though you have done very much as I do - so the lack of germination is a bit of a mystery.  A few thoughts, no real answers though.   
I don't pre-soak the seed.  I don't see why this would hurt - maybe someone else has a thought on this.
I sow the seed around 2cm deep - if surface sown the seed may germinate less well due to the surface drying out and/or exposure to extreme temperature.
I have had losses of some species soon after germination when the pots freeze hard - and this is UK frost.   Central Germany would perhaps have lower temperatures.  Seed in the process of germinating might be killed by frost without the seedlings breaking surface.   In the open garden the effect of freezing is mush less than in pots.
Slugs and snails can make little crocus seedlings disappear quickly but in this case there may be hope if a tiny corm is already formed.
It's worth waiting another year just in case but it's very unusual for 100% to fail to germinate in the first season in a sample of 20.  I would hope for perhaps 75% to germinate.
Hope this helps
Tony

[WimB]

Hi Marcel,

those are really bad results, as Tony said, there are always some which don't germinate (bad seeds) but for me that's also around 20-25%.

I can't really add anything to Tony's remarks. Sowing them at depth is what I do as well. I do soak the seeds for 24h before sowing, which seems to help them germinate a bit quicker. If you soak them you should take care the pots don't completely dry out anymore afterward, since cycling between wet and dry again can be detrimental for the seeds.

And I don't really use sandy substrate, I use 50% regular potting soil (most are still peat-based in Belgium) and 50% sharp grit.

Do keep the pots for one more year though, some might still germinate.

Can't really add anything else, I hope some of Tony's and my advice helps.

[pehe]

Hi Marcel,

In my experience Crocus seeds from the SRGC seed exchange do not germinate the first spring as I often receive them rather late - often in December/January. But the next spring most of them germinate.
Crocus seeds from the Crocus Group seed exchange which is send out in September germinates the following spring.
So my advice is the same as Tonys and Wims: Be patient and hope for germination next year.
For me Colchicum seeds are more difficult to germinate than Crocus, so maybe you could give me an advice for germinating these?

Poul

[Gabriela]

Marcel,
My only interest in growing Crocus from seeds was for Crocus banaticus but in the process I grew few others as well.
As  Poul mentions, and there was also a lot written here in the forum over the years, Crocus seeds sowed in Aug-Sept. will germinate in the next spring; the cycle required for germination is - slightly warm/followed by cold stratification.
So, when the seeds are sown in the winter of course they will need 2 years for germination. You may want to participate in the Crocus group exchange.

I just took a picture today with few Crocus seedlings some of which are almost dormant - all grown from Poul seeds, with many thanks!
C. gramensis and C. nudiflorus (2021) and C. banaticus from 2020. I also grew the spring flowering C. veluchensis with the same results.
I sow the seeds in the most common potting mix and don't fuss about them.

[mannextdoor]

Hello,

and a big thanks for the many replies! So, I didnīt found any big mistake in my germinatio protocol - except the cold stratification was a bit to cold (down to - 10°C). Or, less probably, the subtrate mix is too sandy, gritty. Iīll try a more "normal" mix or simple garden ground (itīs a loamy loess). The pots didnīt dry out any time. I sow them a few days after arrival (and with 24 h soaking in plain water), so, sowing time was mid/end of september. Like i wrote above, for example C. veluchensis germinate in the open beds without problems, dozen of seedlings (the broad leave bulgarian form). Since last year, I participate in the crocus group seed exchange.

@Poul: Iīve only experience with mediterranean Colchicums and species from Israel (obtained from Oron Peri). My protocol is pretty simple (I obtained the seeds in november/december). I soak them in water for 24 h, change the water two times to hopefully wash away some germination inhibiting sunībstances. Then I sow them around 2 cm deep in pots, filled with a gritty sandy soil, conposed from sand, gravel, cocohum, charcoal and loam. Grain size is around 0 - 4 mm. I water them really good (and let them never dry out) and store them in my dark basement. Temperatures will fluctuate, because there is a little window that is always a bit open. I would say, the temperatures go from 2 to 10 °C but mainly around 5 - 10 °C. Germination will occur within 3 - 8 weeks. I use the same protocol for every Mandragora species and I have a germination rate of nearly 100%. A general rule for Colchicum seeds: Sow them as fresh as possible! I also sow slightly brown seeds from the green seed pods with good results. Hope this will help a bit.

@gabriela: Wow, thats a nice germination/seedling picture. Wish, i had success like that...

Greetings from Germany,
marcel