Poor pathetic radicchio

I had never grown arugula and radicchio before. I planted one of each this spring and was **delighted** by the results. So much so that salad has become blah, boring, unfufilling since they have bolted and are no longer available for harvest. I tried to plant more radicciho and arugula in June, but alas, I was too late. Both grew... sort of... but the heat made them bitter, wilted and bolting. Next year, I have to serious re-think my herb garden. I think from the ac unit to the chives, I am going to remove all perennials and re-plant them along the patio. Use that straight space instead as a salad garden... arugula, radicchio, sorrel and mesclun mix. Of course the spinach will stay in the main garden. I need to do successive plantings of all of it. I wish that there was a way to grow salad greens longer... in the shade perhaps? I will have to do some reading this winter.