Conophytum burgeri -- one year old seedlings, about 4mm in diameter.
This is one of the more slowly- growing species,
although no conophytums really grow all that quickly.
You can start seeds at any time of the year, but late summer is probably the ideal time -- the seeds germinate well, and get off to a good start in the warm days and cool nights of autumn. Germination and initial growth seem to be best in light-weight soils with some organic content; I'm currently using one composed of equal parts peat (or coir), perlite and vermiculite. Don't use prepared mixes based on composted peat or bark, which almost instantly degenerate into a slimy mess. Don't bury the seeds, except for a very thin (1 grain thick) layer of course sand. Put the pots where they get bright (but not scorching) light, and cover them loosely with plastic to keep the humidity high. Once the seeds sprout (3 to 10 days), remove the cover.
Seedlings like to be pampered for their first year - give them lots of water and dilute fertilizer, plenty of light, and plenty of fresh air. Wait to transplant them until they start crowding each other out, usually only after they have shed their cotyledons and produced their first true leaves. You should have flowering sized plants in two or three years.
One other note - In the course of my research, I've experimented with sowing conophytums in closed, sterile containers (petri dishes). I have found that this is an excellent way to get lots of seedlings to sacrifice for chromosome counts, but a very poor way to produce healthy, robust plants for my collection -- the seedlings are vulnerable to infections should the container become contaminated, and have a hard time adjusting to life outside when it's time to transplant them.
