The Largest Pitchering Nepenthes
This must be the most asked question I encounter. In fact, it is usually a question I ask of every grower that I come across. "Which Nepenthes produces the largest pitchers for you?"
This is actually not the easiest question to answer, because we growers just keep doing better at growing these plants. The better we understand their requirements and in turn duplicate them, the larger these plants keep getting. 10 years ago, a 17" pitcher was enormous. The past few years I have had plants produce pitchers right at 2 feet in length. The following plants are probably the reigning Kings of Nepenthes as far as species are concerned.
One should not attempt to classify any one of them as the absolute largest, as they are each in a statistical dead heat.
Demand for this plant is high, especially considering the size and color of the pitchers. It is a giant, and probably contains the most fluid of any plant. There have been recordings of up to 4 liters of fluid in field plants. ( Whether or not the pitcher produced this fluid is questionable. Reports of pitchers producing 2 liters of fluid is common. The report of 4 liters of fluid may have been that of a field guide using the pitcher as a water container, in which he filled the pitcher with that much water.) The lid of rajah's pitcher is absolutely enormous. It is large, vaulted, and held high. It just makes the pitcher look that much larger. However, this plant is one of the most difficult to cultivate due to its very cool night time requirements. It's not difficult if you can keep day temps in the lower 80's farenhiet and night time temps in the 50's. Night time humidity should be a saturated and condensing 100%. It is also not a very fast grower, especially when young. The plant should be surrounded by moist sphagnum to allow the pitchers to rest and develop into their massive proportions.
This plant produces giant tub shaped pitchers. It has been known for at least 30 years to produce the largest pitchers in the genus, although this is often disputed. It is a giant nonetheless, and indeed may reign supreme of the Nepenthes. It is much easier to cultivate than rajah, as it is a lowland. It needs a deep pot, for it doesn't like an overly wet medium. Also the large tubby pitchers need a humid surrounding in which to develop their large size.
Known only from a very restrictive elavation on Mt Trus Madi in Borneo, this plant was originally thought to be a form or subspecies of N. edwardsiana. N. edwardsiana is no slouch when it comes to size, but macrophylla was definitely known to be larger in both pitcher and leaf size. The size of the leaves have been reported to equal that of N. bicalcarata. It is extremely spectacular and beautiful, and in the wild it had been reported to produce pitchers as large or larger than rajah. Although its range is higher in elevation than rajah, I find it much easier to grow, and a much faster grower as well. It has become fairly readily available on the market due to tissue culture. Pictures of this plant in Clarke's Nepenthes of Borneo book made my jaw hit the floor when I first saw it. I showed the picture to my 8" diameter N. macrophylla plant and told it to "hurry and grow up!"
This plant is reported at times (usually in an informal off the cuff method) to possibly be the King of all Nepenthes. It's definitely the largest of my growers. Some of my truncata pitchers have reached 21" including the lid. It's more narrow than the above species, and it is by far the easierst of the above Nepenthes to grow. It's a slower growing plant than most, especially as a young tissue culture plant. But the plant produces enormous pitchers from almost day one. It is not uncommon for a 6" diameter plant to produce an 8" pitcher. The plant grows noticably larger with each leaf it puts out, and the pitchers can last for a significant amount of time. If you want a plant that will produce mammal killing pitchers in a short amount of time, then go with a truncata.
Field reports of pitchers measuring 15 centimeters in diameter makes one wonder how large it may get. It probably does not produce pitchers which rivals those of the species above, but it does become the largest Nepenthes plant. It can produce 3 to 4 foot leaves and climb to 50 feet in length. A N. bicalcarata that is 6" wide sporting its vicious fangs would be a truly hair raising plant.
Charles Clarke reports that the giant forms of this plant produces pitchers that can rival N. rajah. Besides rajah, rafflesiana is the only plant to have field reports of large prey being caught. It is probably the easiest species listed here to grow, and the pitchers are beautiful.
This plant for recently found on Mt Trus Madi, and it was determined that it was a hybrid between the giant N. macrophylla and N. lowii, which can also produce pitchers of staggering size. The resulting plant shows incredible hybrid vigor, as the dimensions of the pitchers go off the scale. People who have seen it says it can rival that of a rajah. The pitchers can differ from each other, and some can appear deformed due to the influence of N. lowii's wickededly constricted pitchers. But the pitchers that are not malformed are absolutely beautiful and enormous. Only a few plants are known to exist on the mountain for which it is named, and we can only hope that it will sometime soon come onto the marketplace. It has recently entered cultivation.
A beautiful natural hybrid of N. rajah and N. burbidgea, the pitchers have been reported to be gigantic, possibly rivaling those of N. rajah.
Nepenthes x ??????
Which Nepenthes hybrid could produce the largest pitchers if it existed? Possibly Nepenthes rajah x Nepenthes macrophylla. This plant will have to be produced by hand, as N. rajah has not been found on Mt Trus Madi, the only known habitat of N. macrophylla. Both of these plants have produced hybrids which exihibit size vigor. N. xAlisaputrana, a hybrid of rajah, can produce pitchers that have been reported to exceed that of rajah. N. xtrusmadiensis can produce pitchers that have been reported to exceed that of N. macrophylla. Crossing these two species could create an awesome giant. If someone would like a long term assignment, producing this plant will get you plenty of extra credit.
Hybrids with truncata can also produce very large pitchers, and pitcher features are usually exaggerated when crossing with this parent. Crossing a large tubby Nepenthes with a truncata could possibly produce a giant. N. caruncalata robusta x N. truncata roduces very large pitchers with a nice peristome and are beautifully colored.