it is very easy to grow this species from seeds , if you have good condition .
I think it is easy to grow most species from seeds, if you have good growing conditions - that match exactly for this species.
And it's very hard to grow all the other species that have special needs for substrate, climate or other cultivation conditions.
it is a temperate calcareous plant with a long leaves( some time 20cm like here in my home)
like almost all temperate they make hibernaculae in winter , then for them the dormancy and the outdoor condition are necessary.
I started with a portion of winter gemmae with P. vallisneriifolia in March 2009, and for me this species is very hard to keep alive.
Plants kept in pure peat will die on the long run, so calcareous substrate is essential, as Jeff already said. After I took notice of that, I put them in a mix of peat, vermiculite, limestone, sand and a bit of clay. After two years I had one plant flowering and most others have died.
And the snails are always climbing and sitting on the substrate, I think they are searching the limestone that is not available in my garden otherwise to build their snail shells.
For me, the temperate Pinguicula that can grow in pure peat, are much easier to keep than P. vallisneriifolia which needs a calcareous substrate. I don't know whether it is substrate or climate (or the snails) that they are not growing well for me. This species is shortly before becoming extinct under my cultivation conditions. I'd not call them "easy" to cultivate.
