Question
Hi, I've been growing carnivorous plants for about four years now and I have over 20 different varieties.  Most are doing really well except my venus fly traps.  I know that after a trap wears out it will turn black, but all of mine keep developing black spots which grow larger until the whole leaf dies.  Eventually the whole plant dies.  I have them growing in a 50/50 mixture of peat moss and perlite.  They sit in distilled water about one inch deep, and they receive full sun from 7am until about 8pm.  I don't feed them except what they catch on their own.  I have not fertilized them.  All seven venus fly traps look like they are dying.  They looked sick last summer, so this spring I transplanted them.  They sprouted and grew for a few weeks, and then they started dying again.  Even the new "baby" leaves that are forming are turning black.  Please, if you can help me at all, I would greatly appreciate it.  Thanks.

Answer
Hello-- You probably have two problems: 1) your plant's growing medium is probably too wet all the time, which promotes fungal growth and rot; and 2) you may have a leaf-spot fungus that is growing on your leaves, similar to the leaf-spot fungus that grows on rose leaves and kills them.

The important thing with regard to the leaf spot fungus, especially in areas that are fairly humid, is to try to allow the leaves and the surface of the growing medium to be fairly dry. Initially you can buy a spray fungicide (such as is used to treat black spot on roses) and spray the Venus Flytraps. (Caution: don't use a fungicide based on copper, which is reported to harm Venus Flytraps, but instead one based on sulfur or other ingredients.) After that, don't make a habit of leaving your Venus Flytraps standing in water. Instead, water the growing medium thoroughly, then let it dry out until just moist before watering thoroughly again, allowing the surface of the growing medium to dry fairly completely between waterings.

Venus Flytraps, contrary to popular belief, are not bog or swamp plants. Instead, they grow in very sandy soil in grassy savannahs or pine barrens, where the water table is high but usually not at surface level. Many people that visit the native habitat of Venus Flytraps comment that they are surprised at how dry the soil surface  looks. Sarracenia and many Drosera can tolerate or appreciate wetter soil, but Venus Flytraps grow much better if kept just moist most of the time, not wet all the time. This is especially true during the winter dormancy, because being cold and wet at the same time will promote rot of the "bulb" of the Venus Flytrap.

It also helps to plant Venus Flytraps in larger, especially deeper, pots, which dry out more slowly and don't have to be watered as often. Less frequent watering means more time for the surface to dry.

To ask more questions or get more advice, I suggest joining the FlytrapCare.com Forum--

http://www.flytrapcare.com/phpBB3/

Best wishes,
Steve