1) Clean propagation pans by washing them with disinfectant. Pans should be small and shallow, no more than 4 inches deep and 6 inches in diameter. There are many different suggested growing media formulas to experiment with. One formula calls for mixing a coarsely sifted organic growing medium, such as commercial potting soil, with an equal volume of sharp sand, perlite or pumice for drainage.
2) Pasteurize your growing medium by baking it in an oven at 300 degrees Fahrenheit for 30 minutes. Allow it to cool and wet it thoroughly. Let it drain but not dry out. Fill the propagation pans with the moist soil mixture to about ½ inch below the rim.
3) Sow seeds in the pans around the end of April. Plant seeds as deep into the soil as the seeds are wide and press down lightly. Cover small seeds with a sprinkling of sand to hold them in place. Seed spacing will depend on the species of cactus or succulent you are germinating. Cover the pans with clear plastic or glass. Place them in a bright location but out of direct sun. Keep temperature around 70 degrees Fahrenheit. If soil seems too dry, spray lightly with water. Be sparing. Too much water can drown the seed. Don’t let soil dry out.
4) Watch for germination. Most cacti and succulents will germinate within three weeks but some species require more time — up to a year. When seedling plants appear, raise the cover during the day for ventilation. Watch soil moisture. Don’t allow soil to dry out but also don’t saturate it. Keep temperature between 50 and 70 degrees Fahrenheit.
5) Transplant your plants into their permanent pots. Most cacti and succulents will be ready to transplant in 6 months to a year after germination. The right growth size for transplanting will depend on the species you are growing. Most cacti can be transplanted when they are the size of a large marble. Many other succulents may be transplanted when they are 2 to 4 inches tall. Gently lift the plants from the growing medium, set into the soil of the new container, firm the soil around the roots and water well.