That depends on the individual cow. I've known of some coming back into heat in 20 days. If they are being given good nutrition and they don't breed back within three months, they should be culled and sold.
Get a calendar. Gestation is 283 days more or less. Figure out when you want them to calve next spring. Then deduct gestation length from that date. That will tell you when to turn the bull in. That will get you close-depending on when they cycle after the bull is turned in and if they settle the first time. You should expect them to give you a calf every 12 months.
My a.i tech insists on waiting 60 days. The cows will cycle before then, but he says "the calf bed needs time to heal!" He does get them bred with just one visit doing it his way, and the calving interval is less then a year.
Take Chuck, cowpunk'd, and Caustic's advice. Figure out when you want to calve. Give the cow time to heal 'cuz she'll last longer and give you better calves over the long haul. A cow should give you a calf every 12 months or you need to cull her. There are exceptions to every rule but you need to make sure you don't let too many exceptions ruin your operation.
If you have determined when you want your calves, then the bull is in the pasture with the cows as required (283-285 days prior to the beginning of your calving season). If she cycles, he'll take care of things & if her reproductive tract has healed enough, she will settle (many factors come into play here). On the other hand, if you are in your defined breeding window (time wise to meet your calving season) & doing AI, you should allow at least 45 days for her to heal before going thru the time, trouble, effort, & cost of semen associated with breeding. That is a minimum, I did a couple at 40 days last yr in an attempt of move them up & neither caught. I saw 60 days on another post (certainly should have a healthy repro track given even fair nutrition), but that amount of waiting begins to push the timetable to stay within a 1 yr window (if things don't go well on the first breeding attempt or you miss catching her in heat, or if she was late to begin with then you will not be able to move her up much).
Then again I had a cow that rebred via the bull (one of those mistakes or unplanned pregnancies) at ~30 days post calving.