Question
I have a massive jade plant the I move to a screened in porch in the summer, and back to a southern facing window in the winter.  It has developed hard brown scale.  It is too big and too infected to dab the individual scales with alcohol.  I know not to use malathion, but can I use a systemic insecticide to kill the scale?  I can't spray any insecticide on it until it goes back on the porch in the spring due to it's current location.  Any advise that you can give me would be greatly appreciated.
 Many thanks.
Robin Baither

Answer
Hi Robin,

You can use an insecticide on your plant, but you must select one that is for indoor use.  I am not certain if you have any pets, but you will want to make sure that they do not chew on the leaves of the plant.

If you are looking for something systemic, you can try a product such as Bayer Insect Control Fertilizer Spikes.  I have seen this at one of the big box stores in my area or you can find it online.  This product is effective on soft scales, so am not certain if it will work for the scale you describe. You can find more information here:
http://www.bayeradvanced.com/insects-pests/products/2-in-1-insect-control-plus-f

Another product that I suggest is a horticultural oil.  These are highly effective for hard and soft scales and it works by smothering the scale.   You should be able to find horticultural oil at stores in your area and one I sometimes use is Bonide All Seasons Horticultural oil.
http://www.bonide.com/products/category.php?category_id=3

It is possible that you can remove the scales by gentle scraping, but this really depends on how severe the problem is.  If you spray horticultural oil, be sure to check the plant for reinfestation.  It may take a few applications of oil to get all the scales.  The systemic product will last for many months.

Good luck with your plant!