Hi Christoph,
I received a lowland N. veitchii three leaves cutting last
winter, it sat around in the highland terraruim doing very
little. After I transplanted it into the lowland set-up, it
just grew way too huge. The fourth leaf it grew since I received
was OVER 50 cm. And that's just a small plant! I have noticed
the lowland Neps tend to have pitchers which are small when
compared to leaves and that the highland plants tend to have much
larger pitchers for the size of their leaves...
Dave Evans