I've done one of these with similar infestation and we started off with a 2% and had to bump it up to 4%. We were lucky though as there was no plant material to be concerned with. Those evergreens/hollies in front should be hardy enough so you'll just have to rinse before, during and after. Those daylilies out in front will need to be rinsed as well. But I'm sure you knew this already. We used a pressure washer to do all final rinsing.
Jason , I second what Hank said. If you know you are going to get a good pounding rain soon after, you can just let Mother Nature take its course. If not, a light pressure rinse is handy to have.
Also, be sure to check for water at entrances such as this. Many neighborhood neglected to put in faucets at their entances.
Also some more thoughts regarding jobs like this. Great to do them on evenings and weekends when residents will be passing by you! Make sure to leave signs. Wrapped vehicles are a big plus for this type of work. It there an hoa newsletters you can advertise in?
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