I’d go for it. Here in Massachusetts we’ve harvested tomatoes up through the first week in October, when we often experience 80 degree temps.
I'm north of you, and I am still planting more tomatoes...the last of my black cherries and sungolds are going in this weekend. I hope everyone (plants) deals with the 95 degree day we are being dealt today...back into the 70's starting Sunday...until then; we're broiling. Peppers in 3-gallon containers are inside.
With regards to cooling plants with the hose...I have never had a problem with that...after all; they get wet when you get hit with a spot thunderstorm during periods of intense heat.