Thursday, May 6, 2010

A new pest in the garden

Well, anyway, it's new to me, and I'm just horrified!

To start at the beginning, about ten days ago I put the overwintered plants out onto the deck in a sheltered place to acclimatize. Along with my small but growing collection of agaves, I put out the Meyer lemon. It's still blooming nicely, by the way.

Today, I was checking the potted plants for moisture. I noticed ants had discovered the sticky, sweet nectar of the lemon blossoms and were busily traveling up and down the tree's trunk to gather it. I wasn't crazy about that (the next step is an aphid farm, in my experience), but then I noticed something very different on the stems.
See the little brown bump on the left branch where it joins the others? Scale!

I had never seen scale before, but my heart just knew that's what it had to be.
I ran inside to look up what to do about it. Scale insects attach themselves to leaves and twigs and suck moisture from the plant. They can cause withering, yellowing and black fungus on leaves. The ones I show are females, and the article I found said they are pretty controllable, beginning with taking them off with your fingernail or a stick. If you need more drastic measures, insecticidal soap is recommended. The article warned that you should isolate the plant if it's indoors, because scale is invasive and will infect other plants. I quickly checked the inside plants that were near the lemon, and breathed a sigh of relief: no indoor sign of the little pests.

By the time I took these pictures I had removed as many as 50 scale ranging from 1/16" to 3/16" in length.

Now here's the scary part: suddenly I noticed more. A lot more. Look carefully and you'll see those are all tiny scale insects down the center of the leaf and in some of the side veins above. And that's not the only leaf affected. These pests are all over our poor little tree and they seem to be in all sizes, including microscopic - those females have been busy over the last ten days.

I guess it's time to mix up some Safer soap and get to work. Wish me and the lemon luck!


  1. Oh god...this is very scary. I wish both you and the lemon much luck. I've (knock on wood) not battled scale but is sounds (and looks) downright terrifying. Please keep us all updated!

  2. Ick! Reminds me of when my kids came home from school with head lice. Full report on success rate, please.

  3. yicks! Lemons are tough plants, I'm sure it'll be fine, mine had red spider mite( nasty!) ...I'm just going out to check mine...

  4. Oh, I'm so sorry, poor lemon! Poor you! I have heard this is a super common problem with lemons in our climate. Wonder why? I have tried that soap with aphids and it didn't really work. Lots of warnings on the label... hm. Well, wear a mask. Good luck!!

  5. Hi Jane~~ Dang. You posted this last Thursday and here it is Sunday already. I hope you've eradicated [or irradiated] the little devils. If not, a trick I learned years ago, put the entire plant into a large plastic garbage bag, then spray, then close the bag for 24 hours. The enclosure will allow the pesticide to work its full-strength magic without errant spray or subsequent fumes to contend with.

    Sometimes gardening can be soooooo frustrating, don't you think?

  6. Dealing with garden pests is the least-fun part of this hobby. I hope you win the battle for your beloved lemon.

  7. I have had the same problem with my meyer lemon that now has been banished from the house. Try wiping the scale down, repotting it and then spraying it with neem oil.


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