eggo88

Thanks for such great information. After reading it, I was very interested in getting the 矽藻土 as organic garden insecticide.
I did some online research and found a product (don't know if I were supposed to post the name here) available via Amazon.com.
This product comes in powder form and it is good for a wide variety usages. It can even be added to food for nutrient benefits. By using a dust spray dispenser, one can spray the powder onto trees and plants etc.  
It comes in 20 lbs or 50 lbs size bags.  (50 lbs cost about US $29 plus shipping).
It's not available in Amazon.ca though (out of stock for unknown time frame). But, it's available in some retail outlets.....a sample package of 500 ml for CDN $20.....what a price difference comparing to the Amazon price!

eggo88

Okay, here's the product that I had found online and it's supposed to be organic. One can Google for more information about the product online. (BTW, I am not in any relationship with this company/product.) I have never used or seen this product myself, but found it interesting base on it's wide variety usages as claimed by the manufacturer and with good customer reviews.

So, 版主 please delete this post if you have found such information is inappropriate to be shown here. Thanks.

Perma-Guard Diatomaceous Earth DE Food Grade Fossil Shell Flour.