Article written by Peter Hewitt of Pan's Carnivores. Be sure to read other articles by this South African carnivorous plant guruhere.
Dionaea Muscipula or the Venus Flytrap is the most recognisable of all the carnivorous plants.
I think most of us have killed at least one or two of these fascinating little plants as a child and it is for this reason that most people think the plant is impossible, or at least very difficult, to cultivate. While delivering plants, I have often heard a stern warning coming from the mouth of a well-meaning parent to their excited offspring, not to get attached to the plant they hold in their hands as it will probably die the minute they get home. This guide will hopefully dispel some of the myths and innuendos associated with the Venus flytrap, and give you some confidence with cultivating this gem of a plant.
Venus flytraps naturally occur in boggy areas
Dionaea is a monotypic genus, which means there is only one species within the genus, and that should also mean that all the plants of this species should be similar in appearance. This could not be further from the truth. Through the many years of flytrap cultivation, many different forms, colours and shapes of flytraps have emerged. The plant is native to boggy areas within North and South Carolina, with its main area of distribution being within (roughly) a 100km radius of Wilmington North Carolina.
Dionaea Muscipula as a genus is somewhat under threat in its natural habitat, because of fire suppression and over-collection. The latter problem is somewhat less of a problem now, since plants are now propagated in tissue culture, which is a means of propagating large numbers of plants fairly easily in a lab.
The biggest killer of Venus flytraps, is the misconception that these are tropical plants requiring very high humidity and shaded conditions, much like Ferns or Orchids. This error normally results in the plants struggling along with low light, and too much moisture for the amount of light given. Venus flytraps require a lot of direct sunlight, as this is how they grow in nature. It is true that the habitat of the Venus flytrap is also home to grasses and other plants, which sometimes end up shading individual plants. But the healthiest populations emerge once the areas have received a good burn, which is also a natural occurrence in this biome.
If growing your plants on a windowsill they must receive the right amount of light in order to grow strongly. This plant may start to decline due to lack of sunlight.
Since these are bog plants, it naturally follows that they enjoy a fair amount of water in their growing substrate. The easiest way to accomplish this is to keep the plant sitting in a shallow tray of water which is kept full most of the time. It is a good idea to let the level of water in the tray fluctuate from full, to slightly dry on a weekly basis. You could even keep the plant sitting in water at all times during the growing season, but it is never a good idea to let the water level rise above the rhizome level of the plant. The Rhizome is the fleshy white portion of the plant, situated under the soil level to a depth of about 2-3cm. I keep my trays filled with about 3-4cm of water most of the time, but allow the trays to dry out at least once a week; I leave the trays (not the soil) dry for just a day, before adding more water.
Always keep your plants immersed in a few centimeters of water.
You can cultivate your flytraps indoors or out, as long as you are aware of the plants need for a lot of sunlight (at least 4 hours) and this needs to be direct unfiltered sun. Most of my plants grow outdoors in full sun, and this is where the strongest, healthiest specimens can be found. Some of my customers prefer to grow their Flytraps indoors in a sunny Kitchen windowsill or similar, and this is just fine, as long as the window receives at least 4hrs of direct sunlight every day. Also, try not to forget the origins of your plant in Bogs and seeps, which means the regular filling of water trays lest your plant dry out. If your plant gets a little dry in the media, it is not cause for panic, but if the substrate (Soil) dries out completely, it could well result in the death of your Flytrap. These plants are very tough when given the full light and water conditions they prefer, and thinking of them as delicate and fragile, will not be to their benefit.
Have fund with your choice of container and even combine several different flytraps for a miniature bog garden.
On to the subject of water quality and humidity; since these plants (like all carnivorous plants) come from nutrient deficient soils, they do not appreciate water with a high level of dissolved solids like chlorine and other chemicals. This does not necessarily mean that you can’t water your plant with tap water. In our country, the water quality is somewhat good. Although the water is chlorinated, it usually is not so much that it will cause immediate harm to your plant. If you have the facility to test your tap water, a level of dissolved solids of somewhere in the region of 100ppm is usually safe for Venus flytraps. That being said, it is far preferable to water your plant with water that has been filtered to remove the dissolved solids. You can purchase this kind of water at most grocery outlets and specialist water stores, and it is not very expensive. If you intend to have, or already have a large collection of carnivorous plants, it might be best to invest in a reverse osmosis filtration system, which will remove most of the dissolved solids from the water. This is the device used by most people with a love of these plants who have a large collection. If you do water your plant with tap water, it will be necessary to re-pot it in to fresh media on a yearly basis. The substrate I recommend is simple; 50% peat and 50% sand or perlite is the ideal mix to use. You can purchase ready-made media and containers from Bonsai Tree.
The subject of humidity is also something that might concern the new Venus flytrap grower, but is probably the thing you need to worry about the least. Dionaea can be grown in normal household or garden humidity ranges with excellent results. Even though the area that these plants are native to is very humid, they acclimate down to a lower humidity very well. A general humidity range of roughly 50% or even slightly lower is perfectly acceptable for successful cultivation. There is one point you must consider however. If you purchased your plant from a garden centre or nursery, it probably will have been sitting indoors or in a fairly sheltered position before you purchased it. This will mean that the plant will need to be re-acclimated to lower outdoor humidity over a period of 2 or 3 weeks. You could just place your plant in a slightly sheltered position for a few days, and progressively give it more light each day, until it can stay outside for the duration of summer. It usually only takes a week or two of giving your plant an hour or two of direct sunlight until it will be tough enough to be put into its final position in the sun outdoors. If you intend to grow your plant indoors in a sunny window, it will probably be fine to just place it in its position without any preparation. This is might result in the plant looking a little rough for a couple of weeks, but it will certainly recover.
If possible and if you are keeping your plant indoors, during winter, keep your plant outside where it can get cold and thus provide a good winter dormancy rest for it.
The next piece of cultivation advice I need to give is one of the most important. Your Venus flytrap is a temperate plant requiring a winter rest period. This is commonly called a winter dormancy because your plant will stop growing and most likely retreat down to the soil line looking quite dead. Rest assured; your plant is just underground regrouping its energy resources for the winter. You must keep your plant just damp at this time, and it will return to active growth in spring. One other important point must be mentioned. In spring your plant will most likely send up a flower stalk. It is best to cut off the stalk as soon as it is noticed, as flowering can often exhaust plants in cultivation, which will result in sluggish growth or even the death of your plant. So if you are not a very experienced Venus flytrap grower, it is best to cut the flower stalk off, and your plant can use these resources for strong growth during summer.
The traps of your plant are used to catch insects; you should not attempt to feed it with meat, egg or pieces of cheese. This will result in the killing off of that particular trap and possible damage to your plant as well. It is also not advisable to trigger the traps of your Venus flytrap with your fingers or other object. The traps can only trigger a few times, and when they do get triggered without the intended insect meal, the plant can become exhausted. It will probably not result in the death of the plant as a whole, but will certainly damage the trap and eventually kill the trap off entirely. Let your plant do what it was designed to do. The last important point is this; never fertilize your Venus flytrap in any way. This will almost certainly kill it! The plant is designed to catch its own nutrient, so no fertilizer is needed.
6 Tips in summary
Keep your plant in a very sunny or full sun position.
Keep your plant sitting in a shallow tray of water during the growing season
Water with rain water or water that has been reverse-osmosis filtered. Tap water is not the best, but can be used. Certainly never use mineral water.
Cut off dead traps, just below the trap attachment point.
Let your plant go dormant in winter, at which time just keep it damp. NB: it is not dead!
Last but most important…Keep your plant in a position where you can view it regularly. They are charming little plants that are a joy to grow…enjoy them!