Germinating Mammillaria goldii seeds

I am sowing a fair number of seeds this year, but as yet I have resisted the temptation to try any of the "difficult" seeds like M. goldii, M. saboe, haudeana and M. theresae.

Has a member here developed a reasonably reliable way of germinating these? My researches to date suggest that these species have a hard seed covering that is difficult to penetrate. Some suggest long soaking before sowing, some even go as far as to suggest acid treatment to (presumably) erode the seed covering. But none of them appear to have much data to support the suggested methods.

Can anyone help solve the problem of germinating these seeds?

Greetings from a melting snowfall, hopefully the last blast of the "beast from the east".

Hi Chris,
Hi Chris,
I have read an approach to raising these hard to germinate seeds, particularly m. goldii from a guy called P I Moakes. He suggests you must use seed that has been collected at least 2 years after setting, otherwise it won't be ripe. This might be hard to prove. He then goes on to say that when sowing the seed in must be laid on top of the compost and not covered. After several weeks, even months any that have germinated are left in the pot and the remaining non germinated seed removed to another pot of fresh compost. Reason for the removal is because the soil would by now be heavily alkaline from watering and would create another barrier for germination if left there.

Derek.

Hi.
I have little positive experience in germinating these mammillary.

I want to add at least some useful idea.
It can be sent in the future someone on the right path.

1. Somehow I sowed Sanchez-mejorada. The seeds were fresh and germination 40 %.
2. The doctors have the tool, scarifier. I think it is useful to You. And microscop.
Carefully open the sterile and soaked seed. You need to ensure that the fetus is a life.
The seeds can simply be an empty shell.
3. The sterilization may be performed acid, a strong solution of potassium permanganate, and bleach. These
medications little eat the shell of the seed. A long and thorough rinsing after burn seeds.
4. All these manipulations are made after the first soaking and germination failed.
Mechanical soaking alternating water air. Dripping water, melting snow or ice.
From the word IV.

Vladimir.

If you can read french, there's a nice site that collects the experiences of growers with cacti seeds. The Mammillaria page is on this link:

http://semeurs-de-cactus.fr/index.php/Encyclopedie/genre/key/67

My personal experience is of little use, since I have failed miserably at every attempt to germinate M. goldii. I've had some success with M. roczekii and M. theresae, both with very low germination rates, using my standard baggie method. Although I'm sure they are difficult I suspect seed quality is the most important factor, for these species command a high price and quality/viability screening is probably non-existent for them.

That French site is very interesting and useful. For M. goldii they advise a classic medium instead of a mineral medium. This confirms more or less my own one-time experience. Many years ago, in 2000, a friend of mine had ordered 100 goldii seeds from Köhres. I sowed 50 seeds in a mineral medium, and got only 3 seedlings. My friend sowed the other 50 seeds in a classic sowing mixture and got 20 seedlings.
Two of my goldiis survived and are still alive, growing and flowering well on their own roots (and offsetting). I expect that there will be quite some seeds in the plants, but I have not harvested them in the last years.
I have done some sowing experiments with M. theresae and M. haudeana seeds, collected from my own plants. Somewhat positive results were obtained with a soaking in bleach or a soaking in hydrogen peroxide / vinegar (this generates peracetic acid, which is stronger than peroxide itself). Less positive was the use of concentrated sulfuric acid (concentrated sulfuric acid is 95 -96%). But for M. luethyi, nothing has helped so far.....

Wolter ten Hoeve.