eww! A husker! ;)[my cousin lives in Nebraska] But yeah my plants died because the substrate was to shallow, like you said. They handled moisture well though.
!!!GO DENVER!!
just go buy some raw popcorn seeds. not the buttered up kind in the microwave bag. add dirt and water then boom,little green sprouts! they grow pretty fast. I did it to show my 4 year old brother how to grow things.:)