I've never had any problem with any of the lowland species/hybrids. Highlanders are another story. N. argentiii - I killed two of these and my third I gave it away. N. ramispina ( one of my favorites) my first one died, my second one grew like a weed, flowered, main vine died and then a basal grew before I gave it away. Anyhow I'm sticking to lowlander/intermediates only now. Gave away most of my highlanders. Kept my N. khasiana which grows like a weed in lowland conditions and an N. platychila which is doing well in lowland conditions.