ATTENTION all experienced growers of nepenthes!!!

[traps]

I have a young nepenthes ventricosa. grown in 20,000lummens of light and is in fluctuating humidity between 50 ,60 percent. The top of the pitchers shrivel and the rest of them die. what is wrong and what can I do! Thanks
Mark

[hcarlton]

We'll need more info before we can really help. What kind of soil are they in, what water are you using, and what are the temperatures? Also, if this is a new plant, pitchers usually die off as they accustom to new conditions.

[traps]

ok well it is in a peat perlite mix with more peat. uses distilled water as always with cps. temperature around .70 degrees Fahrenheit and Is a fairly new plant with pitchers about inch long

[hcarlton]

Nepenthes are going to want a far more open mix than peat (generally never a good soil additive with this genus). Sphagnum moss is far better, though perlite in the mix is still a good idea. Temperatures ought to be a littler warmer, as long as it doesn't drop the humidity any more, and if you've had the plant any less than 2-3 months, expect it to drop most or all of its pitchers.

[coline]

I have lost a whole species (multiple clones) for using a really peaty mix, what I use now is something with 30 or less % peat in it, ideally sphagnum, but birds steal it here. So definitely a must do topic.

[joegriffin]

How close to the lights are the pitchers? It sounds as if they are burning.
Not my mix of choice, but I grew a giant Miranda for years in the pure peat it came in. Your mix should work with adequate watering.
What kind of peat and perlite are you using? Miracle-Gro brands have fertilizer mixed in and could cause damage.
Ventricosa is considered intermediate to HL , depending on the type, so 70 does not seem too low.
I, like the others, prefer long fiber sphagnum over peat, and I usually stay under 25%, but it's an experiment that works for you. I would mix in a third of a bark-like substance(orchid bark, cypress, charcoal).
It may just be stressed from repotting, etc. How long have you had it?

[paulbarden]

A 70% peat mix is likely to be far too dense for long term success. Peat is never an ideal choice for Nepenthes, especially if it makes up the bulk of the mix.

[adamcross]

I think vigour and health is more often a function of your growing conditions and watering regime than simply the media, though the latter is obviously still important. Similar to joegriffin, I've got two neglected N. truncata that have been growing happily in the same large pots of 100% peat now for more than seven years; each season they produce huge pitchers and flower profusely, and a couple months back I had to prune several metres of vines off just so we could access that corner of the greenhouse again.

[joegriffin]

Paul, I think you are jumping to conclusions. By what traps said, it could be as small as 51% peat.
;D