Expert: Sarracenia Northwest - 3/22/2011

Question
I lost a lot of my temperate collection to fungus gnat larvae and root rot this last winter. One plant I lost was a Oreophila with 26" pitchers. I've never experienced such decimation before, and I don't want to experience it again. I've cleaned my grow area, removing all the old pots full of rotten bulbs and rhizomes, and I thoroughly washed everything in preparation for some new plants I ordered. I have my old plants that are still alive (and still infected with fungus gnats) isolated in my unheated greenhouse.
Right now I am repotting my S. Purpurea, I plan to give it new soil, but even after I had thoroughly washed the soil off the roots, I spotted an adult fungus gnat. Sure replacing the soil will help. But I am concerned I need to disinfect the entire plant. Is there some safe way to do this, perhaps submerging the plant in water to drown the larvae and adults?
Also, how do you guys treat plants with fungus gnats, and in what ways can I prevent them. Also, have you heard of Azamax?  Supposedly it effectively controls spider mites, thrips, fungus gnats, aphids, whiteflies, leaf miners, worms, beetles, leafhoppers, scales, mealy bugs, nematodes and other soil borne pests.
Thanks
John

Answer
Hi John,

I'm sorry to hear about all plants you lost.  Usually Fungus gnats are an annoyance, not a serious pest.  I've rarely had them affect Sarracenia.

Azamax would be a great product.  It is essentially Neem tree extract which was developed with Fungus gnats in mind.  In your situation it sounds like treating the soil is going to be in order.  I've also had good luck using Orthene, which is a systemic insecticide.  You can still order Orthene powder online. (You mix it in water.)

Tell me a little more about how you are growing your plants.  Some changes in your horticulture could also help curb this quite a bit.

Good Growing!

Jeff Dallas
Sarracenia Northwest
http://www.cobraplant.com