Naturally not all the seeds will sprout. I will plant them all out of the cups in the spring, so no thinning until then (that's the plan anyhow). With the red plastic cups, I can get nine pretty evenly spaced holes so that is what I do, one in the center then eight around the edge. I place the sand on top (1/4 to 1/2 inch layer), the reason is because with the dark homemade compost I use to fill the cups it is often hard to tell when a seed is dropped in, and I found that when trying to make holes in the compost I could not form uniform round holes, but the layer of almost white sand allows me to see the seeds and form perfect round holes when using my crab claw hammer(the little wood kind you get at get at seafood restaurants). Plus it makes it very easy to see tiny new sprouts when they start emerging. After the seeds are planted I just fill in all the holes with more sand.
