Venus Flytraps ( Droseraceae Dionaea muscipula )

Of all the carnivorous plants I grow these are some of the more challenging. For easy carnivorous plants, try a pitcher plant.

Flytraps do very well in terrariums. Any clear covered glass container will work. If you grow them on a windowsill be careful not to cook them in bright sunlight. I take the covers off the terrariums in the summer months.

Fill the bottom with soil that does not have any fertilizer and sphagnum peat moss. A 50/50 combination of sand/peat works well. Soak the soil and wring it out. It should be damp not soaking. Place your flytraps in there, put the cover on, put them under a bright light. They will thrive.

The only other way I have been successful with flytraps is to put them in a clay pot with a soil and peat moss mixture. Put the clay pot in a dish with about an 1″ of water. Water from the bottom, just top off the water every morning.

Fly traps grow slowly. You’ll need to be patient. When they are happy and large enough they will give you really cool flowers in the late spring. They rarely get beyond 8″ in height, most will max out at 5″. The flowers are white and will grow on long stems far above the height of the leaves.

A drafty window is best. Flytraps usually hibernate over the winter. I’ve found the the temperature change near the window is enough to send them into dormancy and wake them each spring. During the winter, keep the flytraps a bit drier.

I’ve found the most important thing for success is high humidity, it is more important than the amount of sun ( which should be as high as you can get)

Deadhead the old traps to encourage new growth. If a trap turns black, remove that leaf.

Do not feed your plants fertilized water or hard water. They will turn black and will die. I use distilled water.

I do not feed mine, I find they fend quite well for themselves.

They hate to be transplanted. (them and every other plant you ever read about) Since there is no danger of over watering them go ahead and put them in a decent sized pot to start with.

There are usually three trigger hairs on each side of the trap, sometimes more. You will have to look closely and catch the light just right to see them. There are also digestive glands on the traps inner surface which release enzymes to dissolve the bugs and to take up the nutrients. These are the red area of the trap. In the outer green edges of the trap are glands that release nectar to attract insects. This part of the trap reflects ultraviolet light that most insects can see.

The trap closes when two or more of the trigger hairs is bent over by an insect in less than a half minute or so. At the base of each trigger hair is a cell that allows the trigger to bend over, it acts like a spring. The upper part of the trigger hair is stiff and unbendable.

The trap rapidly closes when triggered, but leaves small air gaps. Smaller insects escape through these gaps. If a larger insect is inside and it can not escape through the gaps, the trap slowly closes the rest of the way. This is triggered by continuing movement of the trigger hairs or if the prey insect urinates or defecates.

The fully closed trap fills with acidic liquid released by digestive glands. Digestion takes time depending on the size of the insect. Digestion could take as long as a month. The trap reopens once all nutrients have been absorbed. The exoskeleton of the insect remains, waiting to be blown off by wind or washed off by rain. During this time the trap will not re-trigger.

These plants are native to bogs in North and South Carolina which is the only place they are known to grow in the wild. Temperatures there range from ~20’F to 100’F. I tried some outdoors but they couldn’t handle the summers of Houston or the winters of Boston.

Do not buy wild plants. They are endangered. Buy from reputable dealers. A lack of fires to clean out surrounding vegetation, and increased fertilizer runoff has damaged most of the remaining habitats of these plants.

These plants were a favorite of Charles Darwin who considered them to be one of the most wonderful plants in the world. Carl Linnaeus spoke of them as a miracle of nature. John Ellis was the first to describe the flytrap during his travels to the new world. Upon his arrival home there were lines of people waiting to obtain this plant, much like the iPhone lines of recent.

Aphids, mealy bugs, scale and thrips can all be a problem for fly traps. Orthene or some other systematic insecticide is best. Follow the directions on the label. Do not use soap based insecticides.

Black spot and other fungus can also be trouble. Captan is the favorite fungicide right now. You should be able to find it at any plant supply store.


Propagation by seed: I purchased seeds on eBay, get the freshest ones you can. I started mine on peat moss, don’t bury the seeds. They are on a southwest facing windowsill. The room varies from about 100’F in the afternoon to a low of about 70’F at night. I spray them twice a day with distilled water, or cover the container to keep them moist but not wet.

One month old seedlings

1 year old seedlings
Flytraps, 2 yr old seedlings

Propagation by division: Take an outer leaf and gently pull down, you want to get as much of the white area at the bottom of the leaf as you can, that’s where it’ll root. Place the leaf in a terrarium, morning sun, moss, lots of distilled water and you’ll see roots in about a week. You want enough water to keep the terrarium walls clouded up but no water sitting at the bottom. I’ve not yet succeeded at this.



See also:
FlyTrapCare Blog