Can Scale Bugs Live in Soil After Plant is Discarded?

Question

I had an indoor ficus tree that I discarded three weeks ago after battling scale bugs on it for years. I wanted to replant a hibiscus tree in the large pot that the previously infested ficus tree was in. I just filled the very large pot with about four bags of potting soil about four months ago, and hate to get rid of it all. I placed the pot outside in the cold. It is a high of about 25 degrees today. Will the cold air kill any scale living in the soil? Would there be any scale alive in the soil three weeks after the infested tree was removed? Do I need to discard the top layer of the soil? Please advise, I don’t want to infest my new tree.

Answer 1

The cold should kill any scale that might be left, but just in case, you may want to water the soil with a neem oil solution that will kill off any remaining scale. This article will tell you more about neem oil: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm