Ladybugs 1, Whiteflies 0
I have battled whiteflies my whole life and tried many bizarre techniques. These range from covering the plants in plastic and spraying twice the concentration of malathion under it --- (the plants died and the whiteflies thrived) to shaking the bushes with one hand and using by wetvac to suck up the whiteflies mid-air (is it worth it to look so stupid in the garden?!). So you imagine my horror when, on one of my first serious outings into my new home's garden, I brushed up against the boxwood and sent up a cloud of whiteflies. On further investigation, I found them throughout the yard mostly on boxwoods. But this time, with my young grandchildren roaming the yard, I didn't want to use malathion and have that lovely chemical fragrance waft thru the yard for days ... nor did I want the kids to think grandpa had turned dottery trying to vacuum the hedges.
I instead bought 3,000 ladybugs ... the difference between this time and the last time I tried them was that I ACTUALLY READ THE INSTRUCTIONS. As soon as they arrived, they went into the refrigerator (unopened of course). I waited for the forecast of a nighttime temperature in the 50s and then moistened the bushes and the ground at the base. When the sun set, I roamed around on my hands and knees and sprinkled the little gals at the base of each bush --- calling each one by name. At last, when Zelda finally left the bag, I did the whitefly dance and went inside to listen for the chomping.
The next day, there was no sign of ladybugs ... I couldn't find a one ... and now three weeks later, I still can't find any. BUT ... there are absolutely no whiteflies either!