Root rot or blackening of the stem

[NepsAroundTheHouse]

Hey all,
Every once in a while I will have a Nepenthes, usually a 4"-6" diameter plant, that has been established for many months suddenly blacken at the stem, and or growing tendril. Then the leaves start to wilt and blacken and then the plant dies. On a rare occasion the dying plant will send out a sideshoot but often it is too late and the plant dies. What's also unusual is the moss or growing medium doesn't stink or have any "slime" in it. The plant shows no symptoms until one day you notice "hmm....that guy is wilting" and then proceeds to kick it.

I know I've had plants that were sitting in water or kept way too wet rot out. But this occurred with a rajah that was outdoors for over a year! When I checked the root mass, there were plenty of roots and the plant "appeared" fine. From my experience, it's usually the growing tip the turns black first and then the rest of the plant follows suit and dies. This was the reverse. It started on the lower leaves. Any ideas out there?

Joel

 

[agustinfranco]

Hi Joel:

I am sorry about your rajah. These are unique specimens. I have not had that problem. I only had it once, when i used a pot with one central drain hole. This caused my N. fusca to rot. Since then, if i buy a pot, i check that it has at least 5 drain holes at the bottom. if it doesn't, believe me, i make more with a drill. I rather destroy a mere plastic pot than to lose my precious neps.

Two things that may help. First, never sit the plant in water, not even in summer time, only few species love that. Second, get a soil conditioner "trichoderma fungus". Believe me, my plants are doing great!!. The trichoderma will stop any nasties from growing and killing your precious rajah.

Agustin

 

[Tony Paroubek]

Blackening at the growth point vs the root system would be very different.  I usually attribute a growth point blackening to excess moisture down in the tip of the plant for a prolonged period of time.  

Plants dying from the root system up seems to be a fairly rare occurance for me on established plants.  Most cases when I have seen it, there is usually a problem with an unhealthy root system.  Which could be caused by a number of things, from overly dense potting mix, too wet, over potting, deteriorated potting mix etc.  In essence, conditions are better for pathogens and worse for the plant and the damaged roots are an easy 'in' for the disease.

Sometimes a healthy plant comes down with a pathogen and dies.  Sometimes it happens and there is no obvious reason.

Tony