Tropical Pitcher Plants Nepenthes sp.

Introduction to Nepenthes

Tropical Pitcher Plants or Nepenthes are a very interesting and beautiful type of carnivorous plant. There are about 76 species of Nepenthes and 30 of them live on the island of Borneo. Nepenthes usually grow as vines or epiphytes, which are plants that grow on other plants. They look like a tropical, broad leaf plant, except at the end of the leaf on the tip is a pitcher full of acidic digestive juices. Nepenthes use colors and certain smells to lure insects and other small animals into their pitchers so that it can digest them for food. The largest pitchers grow on the Nepenthes rajah. They can grow up to 14 inches long and 7 inches wide. The most interesting Nepenthes fact is that larger species of these plants can digest small animals like rats! Considering the large number of species of Nepenthes and the beauty of these plants, the Nepenthes have been a widely explored and collected.

The Nepenthes plants have traps which grow as a closed container. The trap grows with a sticky, clear liquid inside them that is present before opening, but this is not capable of digesting insects. When an insect is caught in the trap, the trap starts to secrete enzymes to digest the insect. The pitchers use a basic pitfall method to capture pray. As mentioned above, the insect is attracted to the trap by nectar on the leaves and the trap edge. The insect is attracted to the plant and moves toward the trap where the highest nectar concentration is at. When the insect falls in, the plant digests it.

History

The Tropical Pitcher Plant has a most remarkable history. It was the first carnivorous plant to be collected, though it was not because of being carnivorous, but simply its beauty. The written history of Nepenthes dates back 1658 when it was first called Anramitaco by the governor of Madagascar. Various members of the tropical pitchers were described over the next hundred years until a scientist, Linneaus, renamed the tropical pitcher plants with our current name, Nepenthes, in 1737. It took another fifty years for tropical pitchers to make it into cultivation, but about this time, many nurseries were exploring unknown lands looking for rare plants. The Nepenthes certainly qualified!

Cultivation of Tropical Pitcher plants reached peak in cultivation in 1845 after a hefty glass tax was lifted in England. Glass houses were built for the affluent who grew tropical plants including Nepenthes. Several species had been described by this point including the popular N. rafflesiana, N. rajah, N. ventricosa. During this period of rapid cultivation, Tropical Pitcher Plants were shared around nurseries in Europe and America which gave the primary atmosphere to cross breed plants, share plants, and the best part was that wild plant collection was not necessary any longer for the known species.

The rapid popularity and growth of Tropical Pitchers led to many species of Nepenthes being described, and also led to world-wide distribution. This trend continued until 1914 when Europe entered World War I, money and fuel was spent on the war effort instead of maintenance of nurseries. The European populations of Tropical Pitchers nearly disappeared, but Japan began to cultivate these plants which helped to keep them alive. After the wars were over, Nepenthes made a comeback and are well established around the world.

By the time the plants reached cultivation in 1845, it was not yet known that this plant was carnivorous, but twenty years later, a botanist and friend of Charles Darwin named Sir Joseph Hooker, proved the carnivorous nature of this plant. Darwin reported the similarity of this property in his book Insectivorous Plants while writing about the digestive power of Sundews.

Geography

Tropical Pitcher Plants are divided into three basic classes: Highland, Lowland, and Intermediate. The Highland species are pitchers that grow on high mountain tops where it gets cooler at night, but very hot in the day. The Lowland pitchers grow in lower tropical areas with a more consistent temperature. Intermediate pitchers are loosely defined and can tolerate growing conditions under highland or lowland conditions.

Nepenthes grow in tropical areas of northern Australia, Southeast Asia, Southern China, India, and Madagascar.

Growing Specifics

Tropical Pitcher Plants have different growing conditions from other carnivorous plants. These require some special considerations that are detailed below.

Water

The first difference is that the Tray Watering Method will kill your Nepenthes. I keep my plants in the same terrarium as my others (until I make a new one anyway), but I keep them suspended above the water level on pedestals. The plants will need to be watered very frequently to keep the soil moist. If the soil is dry to the touch, the plants should be watered. If the soil dries out, the pitchers will turn brown and die.

Soil

The good news is that the Tropical Pitchers all like similar soils. They like the soil to be well drained, but stay wet. The best way to do this is to include a lot of sphagnum moss in the soil. I add in vermiculite to my mix. Other experienced CP growers add orchid bark, lava rock, or other interesting combinations of big, course materials. Overall, the good news is that Tropical Pitchers can be grown in many mixtures of soils.

Temperature and Humidity

Tropical Pitchers are from tropical areas and need a lot of humidity. The best sources on growing carnivorous plants suggest that the humidity should be at the least 60%. My Nepenthes are kept in my terrarium which has humidity over 70% all the time. The temperature required for these plants will depend on what kind of plant they are Highland, Lowland, or Intermediate.

Highland Nepenthes are the most difficult to grow from my perspective because they require a large temperature change over night. Since they are from the mountains, and mountains get hot during the day and cool at night, your Highland Tropical Pitchers will grow best when they get such a temperature change. Since they like this temperature fluctuation, they do not do very well in a standard terrarium like I have designed on this site.

Lowland Nepenthes like a steadier, but warmer temperatures. They can be ideally grown in a terrarium like I have designed on this site. These plants will tolerate a change in temperature, but they are not as dependent on it.

Intermediate Nepenthes is certainly a vague class, it really more indicates a Tropical Pitcher that will tolerate either of the cases that are listed above.

Photogallery

Click on the photos to see larger images.

Nepenthes rafflesiana This is a fairly common Tropical Pitcher. This is my first Nepenthes which has survived a pest infestation and is now doing well.	Nepenthes rajah This picture was taken at the ICPS meeting at Frostburg, MD.	Nepenthes hamata This picture was taken at the ICPS meeting at Frostburg, MD.
Big Pitchers I do not know what this species is. I took this picture at the ICPS meeting.	Foliage and Traps This picture demonstrates how many traps can grow on these plants as well as how thick the plant leaves can get.	8 Inch Trap This trap is quite large, though not nearly as large as they can get. That is my hand in the picture.
Nepenthes ventricosa 1 My Nepenthes ventricosa with a trap against my hand to show the size.	Nepenthes ventricosa 2 The whole plant.	Nepenthes ventricosa 3 Two traps of this plant. My largest traps are about 5 inches tall.
Nepenthes aristolochioides A young plant. This photo is provided by Colorado Carnivorous Plant Society.	Nepenthes eostachya The Red-Purple Variety. This photo is provided by Colorado Carnivorous Plant Society.	Nepenthes rajah This photo is provided by Colorado Carnivorous Plant Society.

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All information on this site ^©2006 State College Carnivorous Plants. Site designed and maintained by Tom Murosky. Last update January 22, 2007. I allow free use of all written materials on this site. Easy download PDF files availible in the resource link of each plant type. Photographs may contain copyrights from other organizations, you must contact them regarding use of photographs. -- We have had visitors.