N. rajah

Don (dngess01@vlsi.ct.louisville.edu)
Mon, 5 Apr 93 20:50:25 -0400

Here's some info about the cultivation of N. rajah:

N. rajah is a HIGHland species and grows in wet places like swamps or the
surroundings of a waterfall (Nepenthes of Mt. Kinabalu by Kurata)

There's a few lines about it in Nature Malaysiana. I may be wrong (Barry
is now borrowing this magazine), but I think they mention that N. rajah
grows in ultrabasic soils rather than the usual moss-covered rainforest
areas.

The CPN articles you'll want to read are the ones by Thomas Gibson, who is
in the Dept. of Botany at the University of Wisconson (and doesn't 'do' e-
mail as I found out once when I e-mailed the postmaster at the university).
The longer and better article is in the 1983 volume, pp. 82-84. The other
article is in the 1988 volume, p. 84.

A synopsis:
Misting is not essential, but is beneficial. Flow-through water from above
is the best for a vigorous root system. The plant's habitat is "sunny and
wet". At that elevation though, conditions are hazy most of the time with
short periods of full sun usually in the cool morning. Rainfall may exceed
150 cm per year (no wet/dry season). At night, temperatures drop and
humidity rises to saturation. 65-70F during the day and 55-60F at night is
the author's guess for the temperature range. The author says due to
serpentine, the soils may be toxic. Extended periods of heavy rainfall may
oxygenate the peat layer and hence release nutrients stored in organic
matter. Pitcher contents can only be described as a "foul swill" of putrid
insect victims, dead leaves, and twigs.

"During those rare moments when the sun shines, the cloud forest
environment feels like perpetual spring. It is like standing in the
brilliance of the driving cool mist from a waterfall. This contrasts
markedly with the dark, oppressive, hot, stuffy artificial greenhouse
environments created by growers for lowland Nepenthes species."

"In general, I grow N. rajah 'hard' (high light, cool temperatures,
fluctuating humidity, low soil nutrients). In my opinion, it is a serious
mistake to grow this species 'soft' (dark, warm, constant high humidity,
fertilizer in soil). Under such soft conditions, plants produce thin,
oversized leaves and no traps. In this weakened state, they become prone
to stress and disease. From correspondence with my trading buddies, I know
of several scores of N. rajah plants which have died under 'soft'
conditions."

1. Mist plants heavily, at least five times a day (its open bowl pitcher
form has high evaporation rates).
2. Increase light levels just short of burning (traps only form in high
light levels).
3. Feed traps insects, not fertilizer (N. rajah has a poorly developed root
system and fertilizer will not get into the plant readily - instead it will
promote microbial activity which can cause the plant to rot). Feed 1/3 of
the pitcher volume with insects over 10-15 days, which grossly approximates
natural capture rates. A UV light trap will catch pounds of insects which
can be frozen for future use.

He uses Canadian peat moss and white quartz sand (50-50) for a soil. [Good
quality quartz sand can be bought as "pool filter sand" - it should be pure
white and rather coarse. Wash the sand well several times before using it.]