Carnivorous Plants

There is a myth that has grown up around carnivorous plants, that they are very difficult to grow. Does anyone remember the Venus flytraps sold with plastic lids that you mustn't remove. Well, in my opinion they in may ways are easier to care for than most house plants. If kept outdoors, in full sun as they should be, all they really need is to keep them damp, but not too wet.?

Water and keeping them over winter are probably the most important aspects of successful growing.


You can grow carnivorous plants in any container that holds water, gravel tray, saucer, windowsill trough. Grow them on a windowsill, in a conservatory (well ventilated is best), in the greenhouse, or on a patio. Some can be grown in the bog garden. Most carnivorous plants like the sun, especially Trumpet Pitchers, and it is the sun that gives them their best colour.

You could grow them on an old half oak barrel or pot/bowl with no holes. Fill with a 50:50 mix of peat and sharp sand (no fertiliser). Plant with a selection of trumpet pitchers, sundews and venus fly traps. For a natural look landscape with bark or small logs/stone and shred some sphagnum over the surface.


The water you use is very important. Do not use hard alkaline water. This is like poison to carnivorous plants. Use rainwater or distilled water if you can.If your tap water is soft you can use this, or use cooled boiled water from the kettle. Never use mineral water or, water from a softener.

Stand plants in about 3cm of water throughout the growing season. This can be in a water tray or saucer, or just make sure any mini-bog is fairly wet. To reduce watering, make sure the tray is as big as possible. If you have your plant pot in an ornamental container, remember that water 3cm up the pot will not be a lot of water, and you will have to water more often.


The majority of carnivorous plants are dormant in the winter. This is an important resting time for them, when they are not growing, and not really catching any food.Trumpet Pitchers and Venus Flytraps really should be kept cool at this time. If your house is heated, find a cold room, or porch for them to go into. An unheated greenhouse or cold frame is ideal. Make sure its well ventilated to prevent grey mould.You will need to keep them damp, but do not let them stand in too much water (especially Venus Flytraps) Around October pitchers will start to go brown at the top ( this happens during the growing season as well, and is normal). Just use a pair of scissors to cut off the dead bits.Venus Flytrap leaves will go black, and these should be removed. It is important to have a clean up every month or so.

Overwintering your plants outdoors here in the UK can be a nervous time. My own plants are left out to the elements.




If your plant is kept in a sealed environment such as an air conditioned office, you can either catch some wood lice, or buy some small crickets from reptile shop or EBay and yes you can post invertibrates. It is best to use live insects, as when thet struggle it starts the digestive process.

Plants kept outdoors will generally catch all the flys they need however you may catch small invertibrates and feed them.

Fedding them Mealworms is not a good idea as I've had the B$%T*rds eat their way out of a Sarracinia.


Make sure there is no fertiliser or lime in the compost. Use only moss peat not sedge peat. Make sure the sand you use is horticultural, as it will be lime free.Compost mix 1 - for Venus Flytraps Sundews, Albany Pitcher plant
3 parts peat
1 part sand

Compost mix 3 - for Trumpet Pitchers, Darlingtonia.
6 parts peat
3 parts perlite or vermiculite
1 part sand

Most of the Plants listed will grow well in Sphagnum moss. I give mine a short spell on the food processor, thed add sand or perlite.


Carnivorous plants do not suffer from too many problems, but they can get a few:

Aphids - Although these plants eat insects, they can still suffer from greenfly, particularly the soft new growth. Small attacks can be wiped off with a finger, or spray with insecticide.

Botrytis - This fluffy grey mould can cause serious problems on dead foliage particularly if it gets into the heart of the plant. Spring and autumn are the worst times. Remove dead foliage regularly, and spray with fungicide if necessary.

Mealy bug - a small pink grub covered in a white waxy substance. Treat as for scale insect

Scale insect - a pale brown blister on the leaf. These are best treated by dabbing with meths. on a cotton bud, or spray with a systemic insecticide.



Whilst there is no fertiliser in the compost of carnivorous plants, they do still benefit from being re-potted occasionally. Standing in water all the time makes the compost stagnant after a while, and of course, the plants do grow out of their pots. You should re-pot about every three years, and you can divide the plant if you wish. Do not use ordinary potting compost, or ericaceous compost.The best time to re-pot is not in the autumn when they are about to go into dormancy, but just as they are about to start growing, in the early spring.If you are just going to put them in a bigger pot make sure the new pot is no more than 2 sizes bigger than the old (1-2 inches) Ensure the compost is damp, and don't press down too hard when you firm it. The water will settle the plant in.
Put a bit of new compost in the bottom of the new pot. Remove the plant from its pot. You may wish to remove some of the old compost. Place it in the new pot, and put fresh compost around to the same height as it had been in the old pot.Place in a tray of water, and keep out of the full sun for a few weeks. Plants are more vulnerable to disease, especially botrytis, at this time.

Dividing Venus flytraps:

Remove from pot and wash off compost. The plant will separate into little plants fairly easily. Do not force it too much. The long black roots have little white tips. Make sure you don't bend them up in the pot. Re-pot into an appropriate sized pot. Place in a tray of water, and keep out of the full sun for a few weeks.Dividing Trumpet pitchers: When mature, pitcher plants will divide and produce offshoots. The leaves grow from a rhizome, which is the thick knobbly bit, just on top of the soil - it is actually a horizontal stem - with leaves going up and roots going down. Take the plant out the pot and wash the compost off. It will be fairly obvious where the plant can be separated. If you can break (or cut with a sharp knife) some thick rhizome, with its own roots, and a few leaves or buds, it should be all right. Re-pot into an appropriate sized pot. Place in a tray of water, and keep out of the full sun for a few weeks.


These plants can be fairly short lived, needing to be re-juvenated after a few years.

Drosera capensis and Drosera aliciae can benefit from being ruthlessly cut down in early spring. If you want new plants, collect and sow seed, or take root cuttings. The fork - leafed Sundews can make lovely specimen plants in a large pot, or hanging basket, and do well from root cuttings


Once your bladderwort has filled its pot, just break it up into clumps and put it into the middle of a new pot.


The are a bit trickier. They are best grown from leaf cuttings in the spring, or divided when the crown splits (plant has several rosettes, not just one)
P. primuliflora will produce little plantlets at the end of the leaf, which can be potted up. Temperate Butterworts such as P. grandiflora produce resting buds in the winter that can be broken off and re-potted

Cobra lily:

When this plant does well, the plant will fill the pot and start to crawl out of it. It is very east to split the plant up in early spring, making sure each new plant has plenty of root.


The leaves of Sundews are covered in mobile tentacles, each with a globule of sticky glue on the end. These glisten seductively in the sun, looking to a hungry insect, like nectar.
As soon as they land they are caught on the glue and the more they struggle, the more stuck they become. Then phase two is put into operation and the tentacles actually move, particularly those at the edge of the leaf, curling around the victim and moving it towards the centre of the leaf. This is very obvious in the Cape Sundew. The unfortunate prey will either suffocate as it is covered in glue, or if it is very unlucky, will die a slow death of starvation and exhaustion if only its legs are caught.
Once caught glands secret digestive juices to dissolve and then absorb the soft parts of the victim. The leave can be literally drooling during this process.

Probably the best known insectivorous plant, is the Venus flytrap, native to the USA. This plant catches insects in modified leaves. An insect walking on the leaf may touch hairs on the leaf, triggering it to close. This reaction is the fastest known movement of any plant.

The trap will then exeude a digestive juice, dissolving the insect. The juice is then reabsorbed, feeding the plant.

Although there is just the one species in the Genus many colour variants have been bred.

The venus flytrap

The Flytrap has six hair like sensors, three on each side of the trap. An insect touching two of them will trip the trap.

The flytrap's sensor hairs

Another widely distributed insectivorous plant genus are the Sundews.

Sundews have hundreds of stickey hairs which trap the insect, which is then digested.

Sundews are used as a herbal remedy for coughs. here in the UK our three native species dieback to a resting root over winter, re-appearing in the Spring.

Drosera Rotundifolia emerging from Winter dormancy

The Sarracenias, or pitcher plants. They trap insects in a pool of digestive juices.


Keeping Insectivourous plants is quite easy, provided you remember a few things.

The type of water you use is vital. Under no circumstances should you water them directly from a tap. This water usually has addatives, and if you use hard alkaline water, it will kill them. Cooled boiled water is ok, as is rainwater.

Although insectivourous plants need damp conditions, they should not be drowned. An Ideal solution is to stand the pot in a container of rainwater

My own plants standing in rainwater

A fly committing suicide


Allen. C. Roffey Saturday, July 28, 2018 12:19