My plants are dieing and witting...? i have flowers planted in my front courtyard and they were growing...

i have flowers planted in my front courtyard and they were growing and looked really good, but adjectives of a sudden they are dieing. It first started on one side and now its dieing one after another. The leaves are dieing and on them there are white spots. do u enjoy any idea how to stop this??
How to seize rid of cankerworms?
Answers:    You either enjoy thrips or aphids. If they are large white spots that look powdery, you have powdery mildew. Nothing to horrible to control. Get a three within one insecticidal soap/ bactricide and apply as the label directs. I had a bout next to some thrips earlier this year and I used the safer brand (the actual brand name is safer! LOL) and it be under control in in the region of a week. Safer is an organic gardening brand. Works great without hurting the environment! Best of Luck!! It can be purchased at most Lowe's Locations.
Does broccoli grow on trees? how urr...
do the leaves look similar to the green is missing (like a bug ate it)? or, could it be mold/mildew? have you used Round-up nearby that could own run-off?