Hi! In my experience generally any moisture in the buds themselves contributes to the formation of bud rot. I've heard damp soil increasing the risk but I really don't think wet soil alone will cause bud rot in most conditions.
Once buds start forming, stay away from them. There has been debate about lactobacillus/neem treatments where you spray directly on the buds but I wouldn't dare do anything like that. You might as well have a neon OPEN-sign hanging off them :roflcry:
The worst thing I think you can do is spraying anything sugary on the buds/leaves. Think a -50% discount sign right below the OPEN...
My first grow that was outdoors exhibited bud rot after a one night's downpour but the weather in general was really cloudy and humid that week. I did try spraying hydrogen peroxide on there after cutting off infected parts and I think that played me some few days of time.
Now that I've been growing indoors I've had an air purifier from Air-Free running constantly. It removes mold spores from the air pretty effectively and I don't think I could get bud-rot if I tried. The space has to be rather isolated, though, because the purifying action is pretty slow.
I hope I managed to answer your question at least in some way :Sharing One: