Thanks to pobept I now know when to plant a fall crop. He gave me this calculation to plant a fall crop.
date for a Fall crop.
1. Find Your First Average Frost date.
2. – 10 days for seed germination.
3. – days to harvest, (see back of seed package.) Example cucumbers about 58 days.
4. – 30 days to enjoy your Fall harvest.
Plant (10+58+30 = 98 days) before your first frost date..
In many areas July 4 is about the latest you can plant and be assured of a Fall crop before your first Fall frost.
Happy Fall gardening