I use a standard peat mix soil like Pro-mix or Sun mix. The brand is not important as long as it is airy and free draining.
Add soil mix to the pot. This will give you a rough surface with lots of large hills and valleys that are too high for small seed. I use another pot to firm down the soil so that I have a firm flat surface to sow the seed.
Take the seed package, or a folded piece of paper, and slightly fold it to make a funnel. Hold it at a slight angle, and tap your wrist. The tapping action will get the seed to slowly roll to the end of the paper funnel. Using this process the small seed can be spread very thinly over the top of the soil.
Cover the soil with a thin layer of chick grit. Chick grit consists of small pieces of limestone. These allow light to get to the seeds, and they keep the seed moist. The grit will prevent moss or liverworts from growing on the surface.
Water from below so that you do not disturb the seeds. Provide a warm or cold treatment to make the seed germinate.
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