Question
QUESTION: I've been the green thumb on indoor plants in our family for some 15 years.  Last year I was given a large peace lily obviously of a different variety than what I've had before.  Just this week I was trimming away some leaves that had died back around the edges and discovered that many of the stems and back side of the leaves had developed these spots ranging from almost clear to dark brown in shapes that look like a louse bug.  I took the plant to the bathroom, cut off everything with that look, gave it a good shower, and returned it to its place atop the dishwasher.  Any ideas on what this might be?  The only negative influence I noticed is that one of the vents in my house had been blowing directly on it and I've had to water it much more often than my others.

ANSWER: Tammy,

The spots are most likely scale, also an insect. Scale can attack a wide range of plants and can be a real pain to get rid of. You can get rid of it by using rubbing alcohol on Q-tips and flicking them off of each leaf. Then you need to put rubbing alcohol in a spray bottle and spray the plant twice a week making sure you get the fronts and backs of all the leaves and the surface of the soil. Look for the spots that look almost clear, they are the immature ones that haven't formed a hard shell yet. The dark brown or black ones have a hard scale shell over them that the alcohol won't penetrate without using a Q-tip to break the seal. While they are on the plant they suck on the leaves for nourishment and lay eggs to produce more. They can eventually kill the plant. You need to continue treating them twice a week for 3-4 weeks. Good luck.

Darlene

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QUESTION: Do you know where the insect comes from (ex:in the dirt, slips inside opened doors, on clothing) and if it has any people threat or just a plant threat? Also, if my other plants are not touching it, should I be concerned about it getting on them as well?

ANSWER: Tammy,

It can hitch hike in on fruit you bring in or in soil or on clothing from another plant. The infant stage of the insect immediately after it hatches from an egg is able to fly so it can go from plant to plant rather easily. Yes, they can spread from that plant to another but most scale only likes a few plants so it really doesn't spread a lot. However, it is a good idea to inspect your other plants as you water them weekly just to be on the safe side.

There is a product that is a systemic insecticide that is primarily used on outdoor trees and shrubs to control many insects including scale. It is called Bayer Advanced Tree & Shrub Protect & Feed and it is available at Lowes or Home Depot. I have used it on all my house plants and it has not caused damage on any of them and it has successfully killed any insects including scale. It says it will keep plants free of insects for a year but I find it needs reapplied every 3-4 months. You can use thiks or use the rubbing alcohol, either will be effective. With the alcohol you must be persistant. Good luck.

Darlene

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QUESTION: Ah, I bet that's exactly what happened. It's setting was on the dishwasher beside my fruit basket and potato bin.  Won't continue in that mistake!  Thanks so much for your help.  I think I'll pick up some of that Bayer product you mentioned.  Thanks again for your expertise! Happy planting!

Answer
You are welcome. I use it on all my plants. It costs about $20.00 for a bottle but you only use 2 tablepoons per 5 gallon bucket of water or 1 1/4 teaspoon per gallon of water so it will last a long time and it will not spoil or go outdated. If you have more questions later feel free to write again.

Darlene