Answer: You could plant a fall crop of lettuce, spinach, chard, or other greens. You can probably get some short-season broccoli plants to mature--I planted broccoli raab (or rapini), a wild relative of broccoli, and it mature quickly this spring. Another possibility is bush beans--they tend to mature faster than pole beans.
By the way--you might keep some of those annual flowers in the ground--snapdragons and pansies often put on a second show, once the weather cools.
Good luck, and congratulations on your new home!
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