Plants bending over?

I currently have 11 plants growing in an outdoor plot.
They were transplanted from 4" rockwool to soil 4 days ago.
The plants were approximately 3.5 weeks old when i transplanted.
They had filled out the rockwool cubes with roots.
Yesterday I applied safer's 3 in 1, and coated the leaves well.
When I dropped by the plot today, 6 plants had bent their stems towards the ground... drooping and the stem feels soft. I was wondering if anyone knows what could be causing this?
They were started under a 400 watt hps and are otherwise healthy plants.
I am on my way to stake them back up. Hopefully they look better tomorrow.

Thanks.

If it's not going through shock,all you do is find some popscicle sticks or use old May J stems and branchs to help stake the plants upright until the are strong enough to hold their own. Now if they are under stress,then go get some b-1 and add it to water and give the some of that. I stake my life and every grow on that liquid gold!! KEEP SMOKE ALIVE!!

i don't know what this 3 in 1 is, but did it weigh them down enough to pull them over?

Thanks for the replies. I just got back from visiting them and most of them have straightened back up again...very strange...I haven't experienced this before.
I have staked the plants that were still bending. I'm gonna check back tomorrow. the bugs are really bad there... mostly slugs and ants. They were starting to eat the plants so i sprayed them with garlic/pepper/soap mixture...then an unexpected rain..I guess i should have sprayed them again the next day because a few of the leaves were chewed up...then i placed safer's slug pellets around and sprayed them with a safer's 3 in 1 fungicide/insecticide/miticide. Could it have been the 3 in 1?
Would it take 4 days for transplant shock to set in?
If I go back to using the garlic combo, should I spray them everyday? I'm thinking about Neem oil...any suggestions? Any recipes for a home made bugicide?