brooksiefan,
Since you have good foliage going, you might want to back off the MG for awhile and see if this helps set blooms. I had to do this earlier in the season for tomatoes that weren't blooming but were lush with leaves. I usually start off each year giving them (the impatiens) 1/4 doses of MG weekly, then back off once they start blooming so they don't get too leggy. If I'm getting plenty of rain I don't even bother at all with the MG.

I'm surely not an expert and don't know where you've located these plants in your garden, but I get the best luck with my impatiens that get part sun each day -usually several hours of morning sun that doesn't dry them out or wilt them. Direct sun might possibly burn them to ribbons.

Let us know when you get some blooms! -Nan

Thank you, Nan. My impatiens get some morning sun, so I am bewildered. The impatiens I had in the same containers last year bloomed profusely all summer and fall (very mild fall) long.

I guess I was hoping for some sort of miracle cure! Oh, well.

Mine too stopped blooming, I was told to stop using MG, I did and about 7-10 days they started to get buds and flower again. Not as nice as they could be but better than nothing at all.

I think you might find that with oppressively hot days and mostly when the temperatures do not dip into the 60's at night, many plants go dormant (like falling asleep for a while) to preserve energy/moisture. They just seem to stand still until they can be revived by slightly cooler temperatures at night. I started the fall garden tour here in Wilmington NC because I was amazed to see the garden wake up after the heat of July/August and start looking like spring again. With the rain and cooler temps, the garden starts blooming all over again here.
Pauline