Re: CP digest 323

CMDodd@aol.com
Sun, 23 Apr 1995 22:10:44 -0400

Kirk Martin asked about the culture of N. lowii (Trus Madi).

N. lowii is rather widespread in N. Borneo above 5000. It tends to occur in
mossy forest atop ridge lines where it is exposed to a variety of climatic con
ditions. Some of the better known populations are Mt. Kinabalu, Mt. Mulu and
Trus Madi. The Trus Madi form may be more difficult as the plants occur quite
high on the mountain. If the information I have is correct N. lowii occurs
mostly on sandstone derived soils. It is terrestrial rather than epiphytic.
The adult pitchers produce copious amounts of a white cheesey, rather foul
smelling substance between the long lid hairs which may act as a guard to
prevent its easy removal. Ron Determann (Atlanta Botanic Garden) suggested
the pitchers are designed as a water trap. The lowers have the lid hairs
overhanging the mouth and condensation from clouds probably collects and
drips into the pitcher. The uppers are open rain collecting funnels with a
narrow waist to reduce evaporation.
A few natural and manmade hybrids occur.

It responds to the following general Nepenthes cultivation:

Media: equal parts (all fine) horticultural charcoal, fir bark, shredded tree
fern. Media should be pre-soaked for at least 24 hours then rinsed before
use.

Container: 4" plastic pot for seedlings, basket of appopriate size for adult
plants.

Water: pure, less than 40 ppm TDS (total dissolved solids), D.I. best.

Humidity and Air Circulation: humidity should be near saturation at night,
and the plant should receive good air flow by day (greenhouse cultivation).

Light: moderate to bright light (strong here in Florida, but not nearly as
strong as Borneo).

Fertilizer: Don't. My original plant aborted all its roots after fertilizing
with Peter's 20-20-20 1 tbls./2 gal. It took several months to recover and is
occasionaly fed insects now.

Temperature: One of the least understood parameters of highland Nepenthes. In
the field many if not most highland species are under a day/night temperature
CYCLE. During the day the habitat may be quite warm, measurements of the
rocks at a N. rajah site showed temps of near 100 degrees F. at the rock
surface, though roots were much cooler. In cultivation a daytime high of 75
would be ideal, but 82 or so is acceptable. At night the temperature should
drop to 55 degrees or slightly cooler. This cycle is necessary year round.
The plants may be colder in winter (N. lowii and indeed all highland species
have shown no ill effect at 38 F., short periods only), but should not be too
much warmer in summer. Orchid growers have realized the need for this cycle
in high altitude species and it is becoming more widely appreciated in
Nepenthes. Constant cold temperatures do not allow growth and it is believed
that constant warm ones do not allow the plant to process the products of
photosynthesis produced during the day.

Lastly a good dose of a systemic fungicide (such as 1 tablespoon of Clearies
3336 WP) every few months will combat fungus such as cercospora common in
Nepenthes. Follow directions and test on less valuable species. A 4X dose on
test plants caused no ill effects.

N. lowii is my favorite species, it is however, painfully slow growing.

Cliff