Now here's the big factor for pitchering. The weather here ranges from 20-70% humidity depending on the time of year. I do get some coastal fog during the summer mornings and evenings. My highlanders are potted up in pure long fiber sphagnum moss. I keep them in plastic pots and water them once or every other day to keep the moss moist. My plants that are potted up in sphagnum peat moss cannot be allowed to dry out. Peat moss is difficult to rehydrate once dry. Highlanders and most intermediates will produce a shiny waxy outer leaf coat that reduces moisture loss for the plant. 

I normally keep my small plants and new arrivals under shade cloth for the noontime hours to reduce overheating and sun exposure. They do receive full morning sun and / or afternoon sun that they enjoy. Once the plants start vining or getting large, I'll move them to hanging baskets in full sun. Small plants still need to be protected from lower humidity until they get larger.

When the pitchers lose their enzymes, I will use my R.O. water to replenish the lost liquid. The plants don't seem to mind and it usually prolongs the life of the pitcher. This is also the case with new arrivals. New plants are often shipped with the pitchers empty of liquid. So when I pot up the plants, I refill the pitcher with water and that seems to make them last longer. Some pitchers will die while others will last longer.

For my lowlanders indoors and windowsill plants, humidity can be an issue. Lowlanders tend to need more humidity than highlanders to pitcher properly. Some species like N. bicalcarata and N. northiana are notorious for needing high humidity to pitcher and that's why I struggle with them to pitcher in my household conditions. I water my plants when the moss appears dry and drain off the extra water. I use plastic catch saucers instead of clay ones because they don't stain the windowsills. I will leave a little extra water in the saucers for my windowsill plants because they receive more intense sunlight. The extra water creates more humidity around the plant but I never leave my Nepenthes in standing water for periods of time. This will lead to root rot and plant death.

If you use a soil medium other than sphagnum moss, I recommend putting a layer of sphagnum around the top of the soil to create extra humidity around the plant if you're growing it as a houseplant. This increases humidity and can help with pitchering. I've also heard of orchid growers that put their plants on top of catch saucers filled with gravel that has water in it to increase humidity around the plants. I've never tried this but would consider it with my more finicky species.

Finally, ask your vendor how they are growing their plants. Vendors that have taken the time to acclimate and harden off their plants will have excellent advice. Plants recently imported or fresh tissue culture plants need time to acclimate or they can be very susceptible to stress. I've found that whenever a vendor has had plants acclimating for several months before selling them, I have had virtually no problems adjusting the plants to my growing conditions.

General Guidelines

* highlanders can take lower humidity than lowlanders
* larger plants can handle more sunlight that lowers humidity than smaller plants
* adding water to the pitchers when they are empty is fine and will increase pitcher longevity
* DON'T let Nepenthes sit in standing water for long periods of time
* start with known hardy species as windowsill or outdoor growers
* hybrids make excellent beginner's plants and generally tolerate a wider variety of conditions than some species