I put 5 of these seeds in the germination tray along with the New Guinea Impatiens. I think a rule of thumb is to plant seeds to the same depth as their diameter. These seeds are relatively large compared to a petunia for instance. So I planted these Lavatera about 1/8th inch deep in the starter mix. They are spaced right along side the temperature probe. I also turned the thermostat up to 73 degrees today. No show yet on the impatien seeds, but they look like they are swelling! That's the first step.