Expert: Christopher Littrell - 10/23/2007

Question
Hi, I have about 100 VFTs all growing 1 part peat moss and 1 part perlite. All are sitting in rain water.
i live in Auckland New Zealand and I had previously had them inside over the winter months as we had a lot of rain and wind. All were growing really well once they emerged from dormancy. then some of the stems and traps began turning a strange yellow and then blackening gradually. I have since moved the outside onto my deck for more sun and they all look really healthy with great colours of red but still the yellowing traps and it seems about two or three on every plant and most of the time it is occurring on new traps that have bee produced it also seems that it starts when the trap is ready to open. I hope that i have given you enough information and will gladly receive any advice.
Also i have had these VFTs for nearly two years

Answer
Hello Nichole,

First off, great going with all those flytraps.

From what I understand, you moved the plants in and out a couple times and after moving them back outside they started to produce yellowed traps that start to blacken.

It sounds like two possibilities to me.

1.  Since you moved the plants inside, the newest leaves were primed for lower ultraviolet light, so when you moved them back out in full sun, they started growing in, but were burned. The older leaves are still green and red and have not been burned as they are still resistant to ultraviolet radiation. Similarly, humidity changes and wind can dry out bog plants. Venus Flytraps can adapt to low humidity just fine, but a fast change from higher humidity to lower humidity can dry out and damage some of the leaves that have not adapted to low humidity. Give the plants time to recover if this is the case.

2.  Pests could have found your Flytrap garden and started eating on the young leaves before they developed. Aphids, mites, and so forth all like to suck the juice out of young leaves. When the young leaves grow in, they might be deformed, can turn yellow and black, and do not form functional traps. If you see any tiny, black, yellow, orange, or red insects on the central growth point of your plants, you probably have pests.

You can use a water based insecticide with pyrethrines, neem oil, malathion or an Ortho product to control insect pests.

If you have not repotted the plants yearly, their peat moss will break down and rot, creating an infectious environment that will rot the plants' roots, starting off as blackening and sickly new leaves. If by chance they have been in the same peat for two years, repot all of them in fresh mix after cleaning their roots off with clean, mineral free water and if you see any brown or black mushy areas on the rhizomes, apply a fungicide like Physan or Consan to the rhizomes. If the rhizomes are white and/or red colored and firm, they are healthy and probably will not need any fungicide.

Since this yellowing started after moving the plants around, I would suspect one of the first two culprits.

I hope this helps you find out what is affecting your Flytraps,

Christopher