I have been blessed I never had a single gnat the reason for this I believe is the soil I buy is always kept inside at the store if bags are left outside like they do at Walmart it’s almost a sure thing to get them. Even when I buy the bags I keep them in the house a few days before I use it so if there are alive hopefully they die. If you cannot find soil inside and assuming you use soil if there is a way to heat the soil up enough to kill bugs but not hot enough to compromise the soil it’s an idea I just don’t like the idea of chemicals for bugs if possible not to use.
I have been blessed I never had a single gnat the reason for this I believe is the soil I buy is always kept inside at the store if bags are left outside like they do at Walmart it’s almost a sure thing to get them. Even when I buy the bags I keep them in the house a few days before I use it so if there are alive hopefully they die. If you cannot find soil inside and assuming you use soil if there is a way to heat the soil up enough to kill bugs but not hot enough to compromise the soil it’s an idea I just don’t like the idea of chemicals for bugs if possible not to use.