My Nasturtium "Cobra" seeds won't germinate,why?

i am surprised as nasturiums usually do well. I suspect they were either too wet or dried out shortly after they started germinating. when you take one seed out of the pot what does it look like? does it look as if the seed coat has split and the root started and then its dried up or is is soft, mushy and foul smelling?

you may have them at too hot/cold a temperature too. sorry its a very vague answer but these are the usual causes of seed failure.

How the seeds have been kept can also affect their viability. They would not like being kept in a hot shop or cupboard for example.