u/slimepollo555

I harvested the fruit for one of the cochemieas in these photos, i dont remember exactly which one. The fruit had three seeds and i washed the pulp off and dried them, they are currently in a paper envelope, can anyone tell me how to germinate and grow them? I have no experience with seeds, even less with cactus seeds, so im quite lost. Literally any tips or tricks are apreciated, starting with substrate and watering.

I want to get into collecting rare species, im posting here to focus on mesembs (mostly conophytum), even though im also going to be collecting other types of plants (rare small geophytes)

Before i start i want to get a few substrates to make mixes for every plants needs, my current cart (on amazon) is akadama, kiryu, maifanitum, silica sand, and a "calcined nutrient soil" i found on amazon, it doesnt seem to have an specific name, but seems similar to akadama but with nutrients (the one in the image)

These ingredients seem to have everything covered (weight, drainage, nutrients and aeration) but i want a second opinion from someone with experience on these types of 100 percent mineral substrates or anyone who can help me, i want to know if it will work in general, if it will hold enough water (considering that most of the pots will be very small and in full sun/semi full sun) and if i need to add anything or remove something, take into consideration that i wont add anything that floats, because with these kind of very low water plants id like to water by fully submerging the pot underwater to make sure they are fully watered, it will give me peace of mind, what do you think?

Bought it in a local nursery, doesnt have any kind of id

I bought this at a random local small nursery with no id at all, it was the only conophytum they had. Also are those seed pods or just dry flowers? I want to start growing plants from seed and could use some random conophytum seeds as trial before trying to grow rarer species.