Carnivorous Plants/Sarracenia Rhizome Die-off
I have a S. flava AG3 that I got from you guys a while ago and it was doing great all the way up to this winter. It was really big and was enjoying the Oklahoma summers (despite the heat) in full sun. But as it was sending a flower up this spring, we had a huge hail storm that shredded a lot of my plants, leaving me just five of the ten or eleven flowers I was to have this year. this flava's flower bore a little damage, but not too much. Anyway, as the growing season has worn on, its growing points have one by one been slowly dying from the rhizome up. This is super weird because I've been watering them every day and they receive full sun and are growing in your recommended soil mixture. This is also beginning to happen to my alata x minor––it's leaves on some of the growing points are beginning to shrivel as if they are drying out and the rhizome is turning brown. Additionally, when these die back, it's a whole chunk of the rhizome that dies completely–– the roots are still mostly alive but the rhizome on top isn't–– and its made my magnificent AG3 shrink to half the size it started the year out with. What is happening? Is it a virus or a pest even? Thanks for your help.
When this happens 90% of the time it's from Botrytis mold. I can be caused by certain combinations of weather conditions, and the damage you described may have helped introduce it through damage to the rhizomes.
Here's what you need to do. Unpot any of the plants that are showing symptoms. Get a sharp knife or sharp pair of scissors and cut away any parts of the rhizome that are brown. You'll need to be very ruthless about this. You only want to see nice white rhizome material. After all the dead material is gone, saturate the rhizome with a sulfur fungicide spray, then repot in fresh media. Be sure not to use any old soil since it may have the mold in it. After repotting it will take the plants time to recover, but if you don't do this they'll die anyway. Spray the plants with the fungicide every couple of weeks, but follow the directions on the package for dosage intervals. Be sure not to spray when it's hot; late evening is best.
The other pest that could cause your symptoms is Sarracenia Root Borer, but if it's those, you'll see the worm when you cut the rhizome. (They can also help introduce Botrytis.) The root borer is a native pest of Sarracenia and can be treated with a systemic insecticide such as imidacloprid found in Bayer products. If you do find these, do the same thing mentioned above, but I'd recommend spraying with Bayer 3 in 1, since it has both an insecticide and fungicide. Here's more information: http://harvardforest.fas.harvard.edu/papaipema-appassionata-harvey
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