Gardening with Gary

Gardening Advice from an Expert

Venus Fly Trap

Sandy writes~
My Venus Fly Trap sprouted many traps and was a healthy green. We have been watering it with bottled water as recommended. Recently, it finally caught a fly and the sealed trap digested the fly. As it got into about five days of being sealed, it began to turn black at the outer corner of the trap's seal. It spread over the whole trap and is still sealed and black now. Another trap also caught a fly shortly after that and it too now is turning black. Do the traps die once they have eaten a fly or insect? Or is there something wrong with the plant that we need to address.

A. I have a question. Have you sprayed for insects around your home or in the garden not far from the windows and doors? Has a neighbor or the city workers come through and sprayed for mosquitos or anything similar? It sounds to me that the insects have a chemical which is toxic to the traps.

I have grown them and only two times I had one turn black. Once I fed it bologna, a real no-no, as the meat is processed [and has fat] and look what it did to my poor plant! And I still eat lunchmeat! Fool, me.

Or, another time, true, I overwatered one, and the traps turned black and then spread down the stem to the main pant and before I could say Stop, it turned the whole plant a mushy black and dead. They sure do like being on the wet side as they are a low jungle plant. I had mine in a snifter to keep humidity high and cracked it every other day to relieve the beads and give it fresh air.

Always keep dead leaves and heads cut off to prevent fungal infections. Some dieback is natural. Also, do not spring the traps shut often as that depletes the plant's energy and can lead to dead traps. They naturally die back and new ones replace them. In the cool winter, the entire plant may die back but revive in the spring.

Here is some more information for you and other readers here:

The Venus Fly Trap (Dionaea muscipula) is the most well known species of carnivorous plants. These insectivorous plants lure their prey using a sweet smelling nectar. When an insect lands on the head of the fly trap, they seek the source of the nectar, and if the plant is lucky, it will touch one of the many trigger hairs located within the jaws of the trap. Once triggered, the trap snaps closed, trapping the victim. The plant then secretes an enzyme which essentially 'dissolves' the insect, turning it into a digestible dinner. After a few days, the fly trap will reopen, to await it's next victim.

Do not feed the plants, as the flies are enough food for them. From May through October, the soil should be kept constantly damp. Temperatures should be kept between 70 and 95 degrees F. Potting mixture should consist of a mix of 70% peat or sphagnum moss and 30% perlite.

Assistance from: The Garden Helper