A Gardeners Forum Forums Gardening Reference Gardening in 2004 Help! Scale infestation!

I registered for this forum because this seems like a good plant site and I'm hoping someone here can put my mind at ease.

I just discovered that one of my houseplants has a severe case of scale insects. It's some sort of woody, shrub-like plant with palmate leaves (leaflets of 8-9), I'm not sure what it's called. I think the scale infestation is too severe for the plant to survive; the plant was about 2 feet tall, very bushy, and every single leaf/stem seemed to be covered with scales & honeydew. So tonight I put it out on the porch away from all other plants. I wish I had recognized the problem sooner! How quickly/easily do scale insects spread between plants? How worried should I be about the plants that used to be nearby? In particular, some of the infected leaves were touching a Jade plant and a Geranium. I don't see any scales on the Jade or Geranium yet (luckily, I've only owned both for a few weeks), but is there anything I should do as a preventative measure for them, just in case? Other plants I had nearby include a Bird of Paradise, Azalea, and a few Coleus plants. Are any of those particularly susceptible to scale insects? Just how worried should I be about the infestation spreading? Are all of my beloved plants doomed?

hi bugtussle i don't have your answer, but wanted to welcome you. we have several experts taht come around, one will know. in the meantime, enjoy your time with us!

Bugtussle, hi!

I found a couple of links for you that may help..but if the infection is heavy, you may want to trash your plant and keep a close eye on your others...

a couple links for your perusal.. http://www.ext.nodak.edu/extpubs/plantsci/landscap/pp744w.htm#insects and http://www.denverplants.com/foliage/html/Scale.htm

hope this helps a little bit..

Thanks for welcoming me, Jiffymouse!

Thank-you for the links, Barbi. From the info. at those links, it sounds like scales become fairly easy to see after only a few days, so I guess I'll know very soon whether or not it spread to my other plants. I really hope it hasn't.
Yes, I've pretty much decided that the infected plant is so badly infected that it's doomed. Which is sad because I've had the plant for about 5 years now and I've become attached to it. Darn parasites, GRRR! There are just too many of them covering the plant for me to ever hope to win the battle. I'll just have to see if I can find a replacement, even though I don't know what the plant is called.

A good way to get rid of scale is to use Safer Insecticidal Soap. This is pretty much nothing more then a spray soap solution that will smother the little critters when it comes in contact with them. You will need do give the plant repeat applications spacing them apart about 5 days or so. Keep doing this for a period of a month, this will ensure that you get rid of any unhatched eggs as well, before the critters have a chance to lay new ones.
I do agree though if the plants have a very heavy infestation, you may want to opt on disposing and starting over.

Keep in mind that some scale are host specific. So they may not go after your other plants. The key to controlling them is to get them when they are young. When scale first hatch they are tiny yellow dots called crawlers. They are very easy to kill in this stage. But is sounds like you are past that point if you have honey dew production. That also tells me you have a soft scale. Hard scales do not produce honeydew.

Another (non-bio) way of controlling soft scale is take your plant outside and treat with Merit (imidacloprid) you can get it at most garden centers these days. It is systemic and you can get good control. I normally recommend either insecticidal soap or oil but this can be tricky to cover all the nooks and crannies.

Good luck!!

One more option is lacewing larva, and a lot of them if you wanted to go bio-control rout. They may not work as well on large adult scale, but they will get all the crawlers and keep them from growing and reproducing.

Bug Lady,

I didn't know that Merit was labled for scale. It makes sense though. Personally I happen to think that Merit one of the best things out there. It has a high LD50, and since it is systemic, and has to be injested it will not harm any of the benificial insects. About the only thing that would make it better is dropping the price.

Mike