Basic Nepenthes Cultivation

Basic Cultivation of Nepenthes – Tropical Pitcher Plants

Written by Michael Stiffler – mstiffler.necps@gmail.com

New England Carnivorous Plant Society – www.NECPS.us

General information

The Nepenthes are often considered to be the royalty of the carnivorous plant world. Most species are from Southeast Asia, centering on Borneo. They grow in tropical environments with nutrient poor soils, high humidity and precipitation, and moderate to high lights levels – such as open ridges, slopes, meadows, fields, and stunted forests. Nepenthes grow as climbing or scrambling vines with the pitchers, oftentimes very colorful and ornate, borne on tendrils at the tips of the leaves. They capture various small invertebrates (and the occasional small vertebrate) which are attracted by the nectar and color patterns. The pitchers are pitfall traps: insects slip on the wet peristome and fall into a syrupy liquid containing digestive enzymes. For cultivation, an important distinction is whether the species grows naturally in lowland, highland, or intermediate conditions – this primarily dictates the range of temperatures needed for successful cultivation. Hybrids tend to be more tolerant of growth conditions.      

Lowland Species: N. rafflesiana, N. ampullaria, N. bicalcarata, N. truncata, many others

Highland Species: N. hamata, N. edwardsiana, N. rajah, N. lowii, many others

Intermediate Species: N. alata, N. ventricosa, N. maxima, N. sanguinea, many others

Hybrids: N. × ventrata, N. × 'Miranda', many, many others

Cultivation

Soil: Use a loose, open soil that retains moisture but allows drainage of excess water. An easy mix is one part each of long-fibered sphagnum and perlite. Top-dressing with live sphagnum is recommended to provide an indication of adequate humidity and watering – if the live sphagnum looks dry the plant needs watering or humidity levels need increased.

Containers: Must be well-drained and not leach minerals. Plastic pots are most commonly used.

Watering: Use only chlorine free water with low mineral content such as distilled, reverse osmosis, or rain water. Water overhead and allow to drain; root rot can occur if plants are left sitting in water. A top-dressing of live sphagnum is a good indicator of the need to water.

Light: Partly sunny conditions. Artificial lighting (e.g. LED shop-lights) is adequate to grow most species; use a timer to set the photoperiod at 14-16 hrs.

Growing conditions: Lowland species require temperatures of 80-90 ◦F in the day, 60-80 ◦F at night. Temperatures should be cooler for Highland species, 70-80 ◦F in the day, and 40-60 ◦F at night; many NECPS members grow their Highlands in unheated basements. Intermediate species fall between these temperature ranges and are generally more tolerant. Humidity should be high, 60% or above, especially for lowland species – failure to create pitchers is often due to low humidity.

Most growers use a closed terrarium with artificial lighting. Large aquariums are adequate for smaller collections; plants are grown on open shelving (eg. eggcrate) above a few inches of water with air circulation provided by an aquarium bubbler. Most Nepenthes become extremely large – “grow-tents” or greenhouses are necessary for larger collections. A simple homemade grow-tent can be made from shelving covered with clear plastic sheeting. Air circulation can be provided by clip-on desk fans, and humidity provided by an ultrasonic humidifier. For terrarium setups, the sky is the limit with regards to automation of temperature, lighting, humidity, watering and air circulation.

Growing Nepenthes on windowsills can be challenging, esp. due to low humidity. Intermediate species or hybrids provide the best chances of success.

Feeding: Easiest is to use fish foods such as koi or betta pellets, or freeze-dried crickets. One or two feedings over the lifetime of a pitcher is sufficient to fertilize but not overfeed.

Propagation: Easiest to propagate by stem cuttings. See NECPS care sheet “Propagating Nepenthes by Cuttings” by John Phillip for details.

New England Carnivorous Plant Society – www.NECPS.us