Nepenthes Rajah

[NepNut]

Originally Posted by edwardyeeks

In other words, coldness makes more water vapour. Thus, transpiration in the plant does not occur that much since the humidity is high and temperature is low. Thus, highlander neps have adapted to the cold and humid surroundings by reducing the rate of transpiration.

For those who do not really know what transpiration is for, it is to help the plant in reducing excess water and assist in the pull of absorbed minerals and water at the roots to the whole plant. It generally cools down the plant during a hot weather.

A highlander would literally dry to death if exposed to sudden lowland conditions. This is because they have adapted to the cooling surroundings that keep them cool. Highlanders would transpire too much water so that they can cool themselves to match the lowland conditions. Plus, low humidity encourages more transpiration.

Btw, it's nice to be back hi all

Respectfully, I don't agree with your points Edward.

I have some HL species and hybrids, they don't look dry all the time but they still refuse to grow in LL condition. If they can grow, they will just grow new leaves but won't pitcher.

I agree most nep need high humidity to thrive but only HL neps need a drop in temperature or the temperature difference of 10C tp 15C to thrive. There's other reason why intermediates and HL need the cycle for daily temperature drop and IMHO transpiration is only a small part of the reason. I will do some digging as I read somewhere before that certain compounds that's crucial for the development of the plants can only be synthesis in low temperature.