Saturday, January 9, 2010

HELP! - The Dreaded "S" Word

kaffir lime tree
It's been a while since I've posted about my kaffir lime tree, and right now, I wish that I was doing so under other circumstances. I've been noticing for the past couple of months that some of the leaves on my kaffir lime were speckled with some kind of clear sap. I would use a damp paper towel to wipe them off only to find more leaves affected a couple weeks later. Today, I finally got around to researching this and sure enough, my suspicions are accurate. My lime tree has SCALE. Luckily, my meyer lemon tree is located in another room and shows no signs of it.

scale on lime tree
If you enlarge this photo and look at the vertical leaf on the upper-left hand side, you can actually see the little buggers. At this point, the infestation is minor. I'm hoping to find an effective treatment before it really gets out of hand. I've read that the adults breed in the spring. Hopefully I can get this sorted out by then.

I've heard that wiping each leaf with rubbing alcohol is one solution, though I believe you have to do this several times. If anyone out there has any suggestions on how I can eliminate my scale problem safely, please share!


  1. Arghh, so sorry to hear this. My Meyer lemon is suffering the same problem. Thus far, I've been using the rubbing alcohol treatment and it seems to be working, but you need to repeat it every week or so to get the ones you missed. Check the leaves and stems very carefuly, it is amazing how well these insects hide.

    I highly recommend pruning off the thorns before you start this -- painful!

    good luck, and be sure to post any tips you learn.

  2. My sister-in-law recommended the remedy below for the scale on my bay leaf plants. I treated them twice and I haven't seen signs of scale since, but my plants are tiny so were easy to manage. Hope this works for you.

    "1Tbsp dish soap, 8Tbsp rubbing alcohol (to break thru their protective waxy coat) in a 26 oz or 750ml spray bottle, fill with warm water and spray on the plant liberally, especially the undersides of the leaves. Leave on 30 mins then rinse thoroughly (under the tap for a small plant is easiest, outside or in the shower with a hose for big plants....) Then REPEAT every 10 days to catch the bugs that hatched etc."

  3. I just finished up getting rid of scale insects on my ficus bonsai tree! It's the only houseplant that had it, luckily, and it was the only one allowed to summer outside on the deck! Many people use the alcohol thing in my MG group, also soapy water spray works well too, let it sit, then give it a shower, then repeat in a week or so. This time I used a spray I had on hand that treats scale as well as fungus gnats. I bought it for the fungus gnats last year and really liked it. It's called "Indoor Pharm" w/Rosemary Oil, it is said to treat gnats, fungus & scale and so far it has worked! Good luck

  4. I've had scale a few times and it usually is not that big of a problem. Like above I use alcohol, just dip a q-tip in alcohol and take them off. I find I get them in the winter and when the plants go out side they disappear. On some plants they are pretty bad though, I had them on my Clivia's and that spelled the end of them.

  5. Thomas, so sorry about the scales, but when I used to grow indoor plants, I would either wash the leaves (above and below) with warm soapy water and if that didn't cut it, then alcohol on a cotton ball seemed to work.

  6. Hi
    we had scale on our lemon tree in the green house it also had black soot stuff on the leaves. after reading a lot of stuff on the internet we used neem oil with a bit of washing up liquid and water and sprayed it on every 3 days ,doing this 4 times.
    the difference was amazing the scale died off the tree put on huge growth of new leaves and lots of fruit. it looks great now. hope this is helpful.
    good luck

  7. I think that Safer makes a product that i used to get rid of them in the nursery i work for, that is organic, but i cant quite remember...

  8. I also recommend Neem oil.

    Totally unrelated. In South Africa, the word kaffir is a horrible racial epithet, like the n-word here. It is only since reading it again and again in a food context that I have ceased to shudder instinctively when I read it.

  9. Bummer....scale...i've had it on my trees too..can't remember the remedy..i have a friend who is a garden book author and I am going to ask her..she knows everything in plant world..taught me all i know too...i used to work in her shop in Cambria in the early 1980's called Hearts Ease ( named after the jonny-jump -up viola).

    I was thinking of you today, Thomas. I picked up my 2 cherry trees and my santa barbara peach that i had on special order and my liquid amber tree..have been gardening all day. planted red geraniums and yellow violas my clay pots... planted 2 roses to go over my fence..fertilized my climbing roses...raked, clipped back my zinfandel grapes and I had a little helper..a grasshopper...

    i took photos for a post this coming week.....

    i'll ask sharon about the scale...
    more later

  10. Thanks for all of the great advice everyone! I think I'll try the rubbing alcohol remedy since the infestation doesn't appear to be too bad. If that doesn't work, than I'll run out and get some neem oil.

    Good luck with your trees Kary! I'm very jealous! I wish I was picking out trees right now.

  11. The only indoor plants I grow are in my office at work - and they have never had any scale issues, so no help from this source. I hope you get them under control soon.

  12. I use rubbing alcohol as well, it worked for me.

  13. Oh how sad. I think this is one reason I don't grow indoor plants. I hate dealing with pests. I know I deal with the outside ones (especially slugs) but it isn't the same to me.

  14. I once heard that spraying with olive oil works, although I have yet to try it. At least your kaffir is in good shape, our poor tree feel victim to a recent frost....we covered it, really we did!

  15. same as mine. do you have any suggestions how to fix this?! I have been struggling to grow mine as well.

  16. Do you have a specific formula for the concentration of the alcohol used?