Their chinese site appears to have more information however it's a bit more difficult to get around because I have to use the google translator for link/page
I emailed the CKGT and asked if they have sufficient cacti to meet increased demand of their products for the remainder of the year. Per CKGT investor relations the answer was "According to the management, they have sufficient raw material supply".
I also pulled this from the recent 10Q. The "production capability of edible cacti in 2009 was 19,184 tons" from over "387 acres of cactus-farming bases in the Guangdong and Heilongjiang Provinces of China"