Im sitting here reading this and grinning ! I have used Borax to repel roaches and fleas for years. Im way past 60 and am healthy! Sure I never get on the floor or inside my walls to kick up the borax dust then inhale it so I guess Im doing it right! Then I understand caution is best...
Also in a agriculture situation the black plastic is the kill all answer to everything in the soil ! Thats because it works , gets stuff HOT and they die
I use it on my dirt garden every summer..
The nematodes for flea control are great as long as you have the proper humidity in the soil.. if you apply them in the heat of the day and don't water the following day they begin to die right away.. If ordered from Europe the cost is about 80 dollars enough to treat about one acre.. Its been years since I used them because I seem to have gotten rid of lots of dog neighbors! I love dogs ! So I wanted to keep a clean home during the flea season .. That is why I became Mr “kill those bugs”! Also I raised so many reptiles and believe me fleas can be a problem with them also .Lots of reptiles eat rats or mice I had a building filled with rodent cages for feeding purpose . So I had to keep a close watch out for those things.. Because were fleas survive mites seem to endure also.. Its the flea eggs you need to understand have a 21 day cycle so treating every two week 3 times seems to be most effective.. Now having said that I also want to tell you a flea egg can lay dormant for years and with the proper vibration or temperature it will hatch WAMMO where there one there are more so you have another out break of those disgusting little critters.. Hope something I said was helpful
Im no expert just got some real time experence