Nepenthes - also known as tropical pitcher plants or monkey cups - have been inspiring awe in botanists since they were first discovered by Europeans in the 17th century. With their dazzling colours and elaborately decorative traps, the plants seem to flaunt their carnivory with pride.
Ranging in size from diminutive miniatures like Nepenthes argentii to gargantuan monstrosities like Nepenthes rajah, the genus includes the only carnivorous plants known to have caught and eaten whole rats.
The genus is hugely diverse, and some species have stricter temperature requirements than others. Even so, most cultivation advice is broadly applicable to all Nepenthes. What's more, many common hybrids are extremely tolerant growers and make excellent houseplants. Follow this guide and soon you'll need to prune your Nepenthes to keep it in check!
Let's get started!
1. Growing Locations
There are over 170 species of Nepenthes, plus countless natural and cultivated hybrids. Their habitats are hugely diverse, and some are far more adaptable growers than others. For this reason, it’s difficult to offer generalised advice on growing locations which is applicable to all species! However, the guidance below is a good starting point and can be adapted to allow you to grow a wide variety of plants.
When selecting a location for your Nepenthes, there are four main things to consider:
We’ll go through each of these in turn, then look at some common growing locations and their associated advantages and disadvantages.
Most tropical pitcher plants grow in the upper canopy of the rainforest and prefer very bright light, but without much direct sun. Diffused or partial sun is ideal. In the northern hemisphere that could be an east or west-facing window which receives direct sun for only part of the day, or a greenhouse with 50% shade cloth. Too much direct sun can burn their leaves.
Artificial light is also an option. High-powered fluorescent or LED lights (such as T5 growlights) work very well with Nepenthes. I’ve found that LEDs growlights can be particularly effective since they tend to give off less heat than fluorescent bulbs. Spindly leaves and a lack of colouration are signs of insufficient light, while blotchy red marks can be a sign your plant is getting more than enough light.
Note that Nepenthes do not require a winter dormancy, but if you’re growing under natural light, the shorter daylight hours will often slow your plant down significantly.
Each Nepenthes species grows best at the temperatures it experiences in its natural habitat. These temperatures correspond to the altitudes at which they grow in the wild. Remember that Nepenthes are tropical montane plants, and so most require some kind of temperature drop at night.
- For highlanders, this means warm days and cool nights, e.g. 20-25°C (68-77°F) during the day and 10-15°C (50-59°F) at night. These tend to be the showiest species.
- For lowlanders, you’ll need hot days and warm nights, e.g. closer to 30°C (86°F) days and 20°C (68°F) nights. Cold snaps can be lethal.
So-called intermediates sit somewhere in-between, while hybrids depend on the preference of the parent species. One very important thing to note is that hybrids are generally far more temperature-tolerant than pure species. This means that if you can’t provide sufficiently cool nights, your best bet is to try a hybrid or a tolerant intermediate. Many of these will grow quite happily on a cool windowsill.
I maintain a complete list of species - as well as a calculator to help estimate the temperature preferences of hybrids - on my Nepenthes Interactive Guide.
Humidity should ideally be quite high - at least 50% relative humidity (RH) during the daytime, and higher at night. A lack of inflating pitchers on your plant can be a sign of insufficient humidity. Some growers have success using a misting bottle daily to raise humidity. I find it’s just as effective to water little and often, to keep the soil moist.
Many Nepenthes hybrids are particularly tolerant of lower humidity. I’ve found N. ‘Gaya’, N. ‘Bloody Mary’, and N. x ventrata to be particularly forgiving in this regard, along with hybrids involving hairy species like N. veitchii. All of these and more are available for sale from South West Carnivorous Plants. If you’re in the US, you can buy all of these hybrids - and plenty more - from my recommended nursery California Carnivores. Don’t forget you can get a 10% discount on your order by using the code tomscarnivores.
In my experience, it’s also possible for humidity to be too high! Many growing guides suggest that 80-90% is optimal, but I’ve found that keeping the air so close to saturation can lead to issues with mould and fungus, particularly with low airflow. Nepenthes are quite adaptable to lower levels, as long as the growing media is kept moist. You can monitor your humidity using a SensorPush unit, available on Amazon.
When you first start growing Nepenthes, space probably won’t be at the top of your list. Small plants often grow slowly and may take a while to adapt to the conditions of their new home. But if you are successful in cultivating these plants, space can quickly become a problem. Most Nepenthes are climbing or scrambling vines, and when they reach maturity some species can put out nearly a meter of stem per year!
This is worth bearing in mind if you opt for a terrarium or other enclosed space. You can try to source smaller species such as N. glabrata, or slower growers like N. veitchii. Either way, you may soon find yourself having to aggressively prune your plants!
- Windowsills: Some easy-to-grow species and cultivars (see below for suggestions) can adapt to the lower humidity of a bright windowsill, providing their other requirements are met. Regular light watering can help to raise humidity.
- Terrariums: Paired with T5 growlights, a large terrarium can be a great way to grow young plants. Remember that Nepenthes can get very large and will produce climbing vines - these will need to be pruned!
- Grow Tents: Providing you can maintain good humidity levels and avoid your lights overheating the interior of the tent, these can be a great way to grow a variety of species and hybrids. If you wish to grow highland and ultra-highland species but struggle to provide the necessary low temperatures, some enthusiasts have success cooling their tents at night with specially-adapted freezers.
- Greenhouses: A greenhouse heated to a minimum of 12°C and covered with shade cloth is undoubtedly the best way to grow a wide variety of highland Nepenthes species on a large scale - you can read about my own greenhouse setup here. Some growers create warm chambers within their greenhouses for lowlanders.
Back to top.
2. Species and Hybrids
There are over 170 known species of Nepenthes, and more are described each year. What’s more, all of them are cross-fertile with one another to at least some degree. As a result there are many thousands of unique hybrids in cultivation, from simple primary hybrids to extraordinarily complex mixtures of dozens of species. Collecting and breeding tropical pitcher plants can easily become an addiction!
Note that Nepenthes hybrids are often easier growers than pure species plants (on account of so-called ‘hybrid vigour’). As such, don’t limit yourself to just species when looking to start your collection - in fact, starting with hybrids is often a good choice. If you wish to fully explore the diversity of this genus I’d recommend bookmarking both my Nepenthes Interactive Guide and this directory of my own Nepenthes collection.
For now, I’ll recommend some easy-to-grow hybrids and species:
- N. ventricosa x lowii: Also known as N. x briggsiana, this hybrid is a fast grower with red, woody pitchers and an attractively striped peristome. A great alternative to the more common N. x ventrata.
- N. ‘Bloody Mary’: A popular cultivar for terrariums, this is a beautiful hybrid between N. ventricosa and N. ampullaria. It has small, tubby, scarlet pitchers on glossy green leaves, and can grow into a very bushy plant!
- N. ‘Gaya’: A vigorous grower with red and yellow speckled pitchers, this cultivar is N. khasiana x (ventricosa x maxima). It’s a particularly good candidate for a houseplant.
- N. veitchii: A beautiful species and one of my favourites, N. veitchii has traps with wide peristomes and is covered in fuzzy brown hair. It’s particularly adaptable to lower humidity environments, a trait often passed to its hybrid offspring - so look out for hybrids with this species. Be sure to check out my profile of Nepenthes veitchii!
- N. maxima: Red patterning on a green background with a large, flamboyant red peristome (lip). Available in many varieties (including the famous wavy-leaf form), this is an attractive plant which is particularly adaptable to warmer conditions. I’ve written a detailed profile of Nepenthes maxima.
For UK growers, I highly recommend South West Carnivorous Plants. They offer a nice selection of Nepenthes suitable for beginners, including many of the cultivars recommended above.
If you’re in the US, I highly recommend California Carnivores. They have a huge variety of Nepenthes in-stock for delivery throughout the United States, from tolerant hybrids suitable for beginners to exclusive releases of rare collectors’ items.
You can also get 10% off your order by using the code tomscarnivores at checkout.