Non Germinating Mammillaria species

Hi, I am wondering ? In the past two years I have returned to growing cacti from seed after 30 years out of the hobby. I cannot complain, I have planted a lot of seed and as expected mixed results but generally good. However the genus I seem to have the most difficulty germinating is Mammillaria. Maybe its dodgy seed, maybe the particular species need treating in some way. So the ones in particular that I have had trouble with are M. Lauii , two separate forms from different sources - zero germination. M. Grahamii 100 seed batch from Cactus Store - zero. Mammillaria pennispinosa, mammillaria nana, mammillaria hutchisoniana, Mammillaria Toluca - a few popped up but very low rate, Mammillaria Blossfeldiana - 5 germinated from 30 but this was fresh seed from a supplier where everything else was very high germination. There are probably a few others too, any feedback on this seed need to be fresher, older, cold treated etc ? Certainly the group around hutchisoniana / blossfeldiana etc seem to be very reluctant. Seed has come fro Cactus store, Mesa, Koehres and some private Australian growers. Thanks in advance.

Rohan.

Can be on your photo that we see?
What method of germination are you using?

I usually buy 20-30 seeds per serving.
M. blossfeldiana I once sprouted it is very interesting.
One filled two pots, and the other gave a few seedlings.
Conditions of germination and the supplier has not changed.
Lauii, pennispinosa, nana - germinated very poorly or not at all sprouted.
Even if subsequent changes in conditions of germination.
I always have a box in a container with other people's seeds something out of their fees.
And it happens that the sprouts are green only in one place. (guess what).
.

Hi Rohan,

Same question as PVV: What germination method do you use?
The species which you mention should normally give quite good germination. Long ago, I once harvested a dead M. laui in nature (it had probably died because of extreme drought or of frost), and the seeds germinated very well. I had so many seedlings that I even threw away a fair amount of them, which I regretted later on (stupid me) because another fair number of the remaining seedlings died because of a fungus.
It could be that your seed has been too fresh.
But sometimes there are unknown reasons why there is no germination. Example: This year I sowed the red-flowering Strombocactus (seed harvested less than 1 year ago), and put the sowing pot in a propagator. Zero germination. About one month later I put a new quantity of the same batch of seeds in the same pot and in the propagator again. Again, zero germination. About one month later, the last quantity of the same batch of seeds was added to the same pot, which was put back in the propagator under what I think were the same conditions as before (25 to 30 degrees C during the day, no heating at night). This time: very good germination!!! Explanation unknown (moon phase? warmer nights/days, colder nights/days?).

Wolter ten Hoeve.

Thanks guys, I am using the zip lock bag method. I must say I have had pretty good germination overall this season, just those particular Mammillarias seem a problem. Temp was about 22C now averaging more 30C. I must say overall cactus germination has been good but it is Mamms that seem the iffy ones for me.I have since had some Pennispinosa, Hutchisoniana and Blossfeldians pop up, although still less than 30% of seed sowed. Nana and Laui totally refuse, the Laui i've been really keen to get so this is the second source in two years with zero up. I do thing some of the known difficult ones like Theresae which havent geminated could be too fresh. I have herd that Hernandezii needs to be aged before sowing too, though I harvested from my own plants and sowed fresh and had 50% come up. For me, maybe my climate or maybe the seed needs cold treating, Microcarpa, Hutchisoniana group seems to be quite reluctant overall, ah and the Laui, for me at least.

Your germination method seems OK to me, but perhaps nighttime temperatures between 10 and 20 C (daytime 20 - 30 C) might improve the germination. But I guess that you already switch off the heat during the night.
Could it be that seeds of certain species don't germinate well in the spring in the southern hemisphere, and would give better germination there in the fall?
Do you import the seeds and are they perhaps being irradiated at customs?
M. hernandezii: I put them in a shaded and cooler place from the beginning of August. In that way, the bud formation is partially postponed and I get some flowers in the spring, which can be pollinated and then form fruits in the fall. The seeds from these fruits germinate quite well in the next spring.
M. theresae, goldii, luethyi, etc.: Terrible germination (zero or just above), I don't have a good method. During the last ELK in Belgium, I asked a Czech, who sold many M. goldii seedlings on their own roots, how he got all those nice seedlings. He told me that he chemically killed the plant and extracted seeds from the decomposing matter. Because I was not yet going to try his method on my two seed-grown goldiis, I preferred to buy some goldii-seedlings from him.

Wolter ten Hoeve, The Netherlands.

Thanks..That is very interesting. Where I live I sow early November, I do not use heat, my seed trays are in a window but last year they either got too much sun or not enough so this year I have pulled down the blind and growing under an LED light bar instead and leaving it on 12-14hours a day. Seasons seem to be getting later each year and it stays cool for a month longer than it did a decade or so ago. Early november here was  20 -25C day on average and 12c average at night, that is when I first sowed and most seed came up within a week, but only a few of those were Mammillaria. After 4 weeks the temp was more 30C day and 15C at night, still few Mammillarias. After 8 weeks, by which time we have had some 30-39C days and I had not looked at the seed bags fore two weeks suddenly some M. Albicans, Blossfeldiana, Hutchisoniana and Pennispinosa v Navacensis appeared, maybe 5 or 6 of each out of 20-30 seed, not great but enough if they grow strong. Maybe a few more will pop up late. Thinking back to last year my M. Sempervivi and Chionocephala did take 4 weeks or more to germinate but have outstripped most others sowed and are almost ready to pot on now. M. Guelzowiana was the best, germinated quickly and have also grown very strongly. I have sowed Theresae and Goldii this year and none germinated so they are staying true to form it seems. Maybe they just need to be aged and acid etched. Also last year I sowed a form of M. Grahamii (100 seed) which was stated as being collected in Texas, not one came up. I have wondered if possibly some of the USA ones may need treating like Sclerocactus etc, sowed mid winter when cold. I wondered this about the Laui v dasyacantha too being high altitude.

These points bring me to the following: Could it be that the seeds of certain species have a built-in clock and/or thermometer?
For species from the highlands of Mexico, there are always cool nights and almost never very hot days. Rain can fall during the whole summer and into the fall. This might mean that there is no specific favourable germination period.
For species from Sonora, Sinaloa and SW USA the winter cold and drought lasts quite long and that's not favourable for germination. Rains come mainly in July and August, and I think that this rainy season is combined with hot days and warm nights, which is probably favourable for germination. It might mean that species like grahamii, mainiae, etc. can better be sowed when nights are not too cold.
For species from Tamaulipas there can be cold spells in winter and spring, but not as long as in the northwest of Mexico/ SW USA. Rains can fall in any month of the year, but mainly from April - June and in September. The Tamaulipas species generally get quite a lot of rain during the year. Maybe, sowing the Tamaulipas species a bit later than the highland species is worthwhile.
All the above is just theory!

Wolter.

Thanks, it is interesting. I have read a number of scientific articles on Cactus germination and without going into detail have realised that just because seed does not germinate does not always mean the seed is unviable or not fresh. With failed species I am more likely to try again and research possible better timing/seed prep etc rather than give up.

Progress report on low/no germinating Mamms. Firstly all are still enclosed in bags but the bags have been replaced twice under semi sterile conditions, as one would when sowing.. to reduce excess moisture content. Pennispinosa var narvasensis only had about 4 up after 6 weeks. Somewhere around 12 weeks suddenly a heap germinated ... yay. Blossfeldiana, Albicans and Hutchisoniana, only a few of each came up, now as we enter Autumn all of these are showing more germination just now. Possibly the weather got too hot during the first attempt. Nana, Goldii and Lauii were removed from bags, dried and refrigerated for a bit. Will try those pots again soon. I know the Goldii can take many repeat tries, so not giving up on those .

Been a while, but my pennispinosa are quite a large trays worth ... they germinated very patchy over at least 9 months but even the last germinators seemed to handle the drier conditions and progressed. Since bought another hundred microcarpa seeds from Koehres and still 0 germination, I dont blame the seeds, maybe my conditions. purchased 4 different Laui from elsewhere and had reasonable germination, once again many delayed 6 months will have to catch up. Toluca ?? I posted this in my original post as a non-germinator .. I have no idea what I was referring to as I've never tired Toluca seeds !