Question
QUESTION: I've been dealing with a never ending aphid problem in my sundews and butterworts. I've been using pyrethrin to kill the little pests but it seems to be causing damage to the new growth on my butterworts, and making the sundews dewless. Does this mean that I shouldn't be spraying the leaves on the plants? Also the aphids just won't ever go away, I've been fighting them for a couple of months now. Are there some other alternatives I should look into to for killing the aphids?

ANSWER: Hi Garrett,

Sometimes the carrier of a particular brand of insecticide can have compounds that damage leaves.  It can be a wetting agent (surfactant/detergent) that helps the chemical to stick to the plant better.

Here's some things you can do.  First, just spray the crown of the plants, not the open leaves.  Usually the aphids are just attacking the middle anyway.  Try spraying at night.  When it's cool you often get less damage.  You could also try a systemic like Bayer Rose and Flower insect killer.  It contains imidacloprid, and it would last for about 1 month.  I've never had any issues of leaf damage with it.  

If you seem to have a bad aphid infestation you must have them all over the place.  You could also try using a No-Pest strip if you have a room or enclosed area where you could hang one.  Just make sure it isn't a place where you hang out for extended times, or use it in an enclosure with the plants.  They send our a vapor to kill insects.

Good Growing!

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

---------- FOLLOW-UP ----------

QUESTION: Unfortunately the crown of the plants (mainly the butterworts) is where the chemical damage seems to be occurring. The older leaves are often unaffected by the insecticide, its the newer leaves that are seeing damage. My Pinguicula laueana was just fine the day before I sprayed it, and leaf damage showed up the next day on the newer leaves and developing flower. Is it possible to just apply to the soil around the plants so it is absorbed by the roots and not the leaves?
The no pest strip is not an option since I my plants are in my dorm room with me. If i can find the Bayer Rose and Flower spray I would be tempted to use it since it would not harm the plants. Do you have any other suggestions on aphid prevention?

Answer
Hi Garrett,

Right now, the systemic insecticide sounds like your best bet.  Stop using your current product since it doesn't seem compatible with your plants, and since it's not a systemic, it won't be absorbed by the plants roots.  The Bayer has almost no odor, so you shouldn't find it offensive in a dorm room.  This is the specific product:  http://www.bayeradvanced.com/rose-flower-care/products/dual-action-rose-flower-i

Good Growing!

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