How long after blackberry bushes bloom does the fruit ripen?

Found hundreds of plants in the woods and I really would like to pick some when they ripen but was wondering how long I should wait before heading back out there with a bucket.How long after blackberry bushes bloom does the fruit ripen?
In temperate climates, blackberries are in flower from the end of June until mid-August and ripen from around the end of August until mid-October. Usually, I go and pick berries around the start of September. There was an old superstition in Europe (mainly the UK) that you had to pick berries before September 15th (around the time of Michaelmas) because after that date they belonged to the Devil and would be covered in his spit. Certainly, a wet September causes mold growth on the berries and therefore the best are to be had at the end of August and start of September. It's also a good idea to pick them before the first frost as frost causes them to go mushy.How long after blackberry bushes bloom does the fruit ripen?
Here , ( upstate NY) they start blooming in mid-June , and start ripening at the end of July , with the the bulk of them in mid-August , So 1-1/2 to 2 months. If you are in a warmer location, it will probably be a little quicker .