Red or Green Venus Flytraps?
People often ask why their traps are red whereas their friends are green. The reason some traps are green is due to a lack of light. Healthy plants exposed to lots of light (which they love) will generally turn red, whereas those in inadequate light will stay green. The more light, the redder the traps will get.
Some varieties of Venus flytrap are more noticeably red than others, in particular:
- Red Dragon
- Colin’s Red Sunset
- Red Piranha
Whereas some varieties such as Justina Davis have little or no red colouring at all, no matter how much light they get.
In general, the more red colouring a Venus flytrap has, the slower it will grow as it isn’t able to photosynthesise as effectively (photosynthesis requires chlorophyll which is what makes plants green).
Venus Flytrap Cultivars
The International Carnivorous Plant Society (ICPS) maintains a list of registered cultivar names for Dionaea muscipula Soland. ex Ellis (aka Venus flytrap).
From Wikipedia: A cultivar is a cultivated plant that has been selected and given a unique name because it has desirable characteristics (decorative or useful) that distinguish it from otherwise similar plants of the same species. When propagated it retains those characteristics.
Here is a complete list of all of the current Venus flytrap (Dionaea) cultivars registered with the ICPS.This list does not include those cultivars which are not fully registered with the ICPS such as Dionaea ‘Clumping Cultivar’, Dionaea ‘ Big Mouth ‘, Dionaea ‘Kinchyaku’, Dionaea ‘Red Rosetted’, Dionaea ‘Royal Red’ etc.
Dionaea ‘Akai Ryu’ – aka Dionaea ‘Red Dragon’
The most common red form of the Venus flytrap. Is known for it’s intense dark red colouration.
Dionea ‘B52′
Currently considered to the largest Venus flytrap cultivar. Optimal growing conditions are required for these plants to reach their full size. Poor growing conditions will result in a plant the same size as any other.
Dionaea Clayton’s Red Sunset
Red with long skinny petioles (particularly during winter) whereas other red cultivars have quite wide petioles. They often lose all of their leaves during dormancy.
Dionaea ‘Cupped Trap’
The traps are joined at one end, creating a cup shape. Despite their warped appearance the traps still function correctly.
Dionaea ‘Dentate Traps’
The spines of each trap are short and triangular like a sharks tooth instead of long and skinny as in ‘regular’ varieties. The spines of small/younger plants do not shows these properties as prominently.
Dionaea ‘Fused Tooth’
The spines of the traps are bent out of shape, fused together by webbing. The traps usually look normal during spring however.1
Dionaea ‘Green Dragon’
This is believed to be a mutation of the ‘Red Dragon’ cultivar, but the edges of the traps do not turn red, even when exposed to intense sunlight.
Dionaea ‘Holland Red’
A red variety which is often green when growing in insufficient light.
Dionaea ‘Jaws’
The traps are very big and have short, pointy spines.
Dionaea ‘Justina Davis’
The traps are always green, even when exposed to intense sunlight.
Dionaea ‘Louchapates’
The spines of the traps are split and found at the ends of the trap lobes.
Dionaea ‘Petite Dragon’
Has the same deep red colour as Dionaea ‘Akai Ryu’ but is not as large and has bifurcated flower stalks.
Dionaea ‘Red Burgundy’
A red variety which is known for having rapid growth characteristics (for a red variety).
Dionaea ‘Red Piranha’
Has short, triangular spines like Dionaea ‘Dentate Traps’ but the intense dark red colouration of Dionaea ‘Red Dragon’.
Dionaea ‘Sawtooth’
Similar to Dionaea ‘Dentate Traps’ but with trap spines which are modified into short, sawtoothed edges.
Dionaea ‘Wacky Traps’
The leaves are incompletely developed. This is an extremely slow grower that also has strangely distorted flowers. Known in some circles as “Bart Simpson”, but this name has not been established and might even violate some trademark laws.
Cultivar Groups
From Wikipedia: Under the botanical nomenclature of the International Code of Nomenclature for Cultivated Plants (ICNCP), a cultivar group is any gathering of cultivars designated by common traits.
Dionaea Dentate Traps Cultivar Group
This cultivar group contains all plants with short, triangular shaped spines.2
Venus Flytrap Taxonomy
There is only one genus of Venus flytrap … Dionaea muscipula Soland. ex Ellis. However there are many different varieties of this one species.
Most cultivar species are distinguished by the colour of their traps, their trap shape and the size of their traps. Traps with strange shapes such as short or triangular shaped spines, deep red colours and abnormally large traps are often given their own names.
For detailed information on the taxonomy of carnivorous plants I recommend checking out Barry Rice’s carnivorous plants taxonomy page.
Flytrap Growing in poor conditions – Week 6
Our experiment has entered it’s sixth week and will be shortly heading into the middle of the summer when they will be exposed to the most sun.
The test plants are looking fairly healthy but have lost some of the red colouration from their leaves in comparison to our control plant which is in a sunnier area. The maximum trap width of all of the test plants has not changed measurably so far.
Specimen A: Low light, distilled water
Specimen A, which is being watered with distilled water and grown in a low light environment is looking okay, but it’s leaf-base is weakening, causing the trap with the longest leaf-base (bottom right in above photo) to droop towards the ground. The initial angle was approximately 30 deg. from vertical, however it is now closer to 30 deg. from horizontal. This plant has grown an extra trap and a further three stems are growing. Unfortunately, one of the new stems has begun to turn black. A fly was fed manually to this plant one week ago, the trap is yet to re-open.
Specimen B: Low light, tap water
Speciment B, which is being watered with tap water was manually fed a fly one week ago, it’s trap is beginning to re-open. One of it’s traps was triggered, but did not catch a fly, this trap re-opened within 48 h. This plant still has three traps, but another trap is in the process of opening and another stem will probably be forming a trap soon.
Specimen C: Control Plant, medium light, distilled water
Our control plant speciment C, is looking nice and healthy and has caught a fly naturally and been fed one by hand, both times the traps re-opened within five days. The red colouration in the leaves is not as intense as they were at the beginning of the experiment, but not hugely so. The total numbers of traps is still six, however their leaf-bases are noticeably longer than when purchased.
Conclusion
This is early days yet, so there’s not much that can be concluded from the results so far. However initial results are showing are indicating that the control plant (specimen C) is coping with it’s new environment better than the two test plants in dim light (specimens A and B). Specimen B which has been watered with tap water appears to be slightly healthier than specimen A which has been watered with distilled water.
Information will be posted here eventually with information about the amount and composition of dissolved solids in the tap and distilled water used for this experiment and the approximate daily average light intensity that the plants are exposed to. So check back later or subscribe to our RSS feed to keep up to date with the experiments progress.