The first thing you will need to breed boas is a definite adult pair, males 18+ months and 4 feet, and females 3+ years. Both boas need to be in top condition, not fat or thin, but in peak condition.
I don't breed my boas like many others do. I don't try and force a breeding season on my boas. Cooling may work some times but it can be very hit and miss. I believe that a female boa will come into "season" at any time of the year. Something tells her that her body is ready to reproduce and the follicles that she carrying dormant throughout the year begin to grow. This is the time that she will be producing pheromone to attract males. It could be winter, summer, fall, or spring. Regardless of the time of year it is when the female is ready that courting will begin.
I basically introduce my males to females periodically throughout the year, and either they will be interested after a few days, or not and I remove them and put them back in their own enclosure. Is it that simple? I wouldn't call it simple, Boas are not going to produce every time just because they went through the motions of courting and copulating, there is an element of luck involved. Just when you think you have got it all figured out they will throw something new and different at you to put you back in your place...LOL...
I do have a cycle in my boa room, there are temperature differences throughout the seasons, they are not drastic but the ambient temps fluctuate a bit with the seasons. During the winter months the cool side of the enclosure may get to the low 70's at the coolest part of the night, and mid to high 70's during the day. There is always a hot spot ( basking spot) that is between 88-93 degrees through out the year. Spring and summer the ambient (cool side) temps may be in the low to mid 80's depending on the time of the day. I have a light cycle also that is set to mimic the outside light for light hours give or take an hour or 2 depending on the season.. For example I may have the room lights on longer during the winter than the actual daylight hours because here in WA state it gets dark mid winter at about 4:00 pm.. The natural light from outside is the major factor in the lights anyway, I am sure the boas can sense it is night even though the lights are still on. Let natures own cycle work in your favor.
After they are introduced, the male usually goes into the females cage because of the fact that the females have larger cages do to their greater size. Sometimes courting will happen right off, and sometimes you may have to pull the male if he shows no interest after a few days. Reintroduce him in a week or two.
Once courting has begun try to give them some privacy, watching from a distance for signs you may want to note in your records. Any activity you think may be important write it down and be sure to note the date. Make sure you write it down, I have done it myself thinking I'll write it down in a few and then forgetting all together.. Some males will get right to copulating, and some may take weeks to "convince the female" he's the male for her. Try to be patient.
Usually copulation will take place a few weeks prior to ovulation. Ovulation may be obvious or subtle, and may look like the female has just eaten a large meal. The swelling will be further back than a large meal would sit right after eating. If you see or suspect your female is ovulating write it down with a date. Babies are born an average of 125 days after ovulation. Sometimes the female will shed within a couple of weeks of ovulation, this is called the post ovulation shed. The post ovulation shed happens most of the time, but is not as accurate as noting the ovulation date, and may not happen at all. When calculating the birth date by the post ovulation shed, birth would be approximately 105 days afterward. It doesn't always happen by the book, boas can't read, so if they go a few days longer or shorter don't hold it against them..
After the female has definitely ovulated you can remove the male, and start to raise your temps back to normal depending on if it's during a cooler point in the season or not. Summer time temps are best for a gestating female. The male will usually be uninterested in the female by this time. If you are not positive that the female has ovulated, it wouldn't hurt to leave the male in with the female for a while longer. Try feeding him, and her separately, and try reintroducing him again in a few days.
Gravid Female Care
If your female is gravid she will bask on the hot side most of the time. Be careful not to feed the female too large of a meal, keep the meal size to a minimum. I don't feed them at all during the last month gravid, to keep them from giving birth prematurely. Be sure she has plenty of clean water, and her temps are correct (don't trust 1 thermometer). I give my females some crumpled news paper to hide under to reduce stress. Try to keep her cage as clean as possible with out disturbing her. I only clean one side of the enclosure at a time, which ever side she is not on. Don't handle your female while she's gravid, she won't like it and may just let you know with a bite! Give her as much privacy as possible, and get ready for those babies.
TIPS FOR GETTING A PICKY MALE BREEDER TO START COURTING....
Adding a shed skin from another male may make your male want to compete, and get him to court.
Using another male to spar with your male may work also. Only do this while watching, males can become aggressive toword each other, and you want to be sure you know who's the father of the babies.
Try some night misting with luke warm water.
Take your male out and feed him a small meal, maybe he's just burnt out, and needs some energy.
Add some used paper from a females cage that is ovulating.
Make a privacy screen, something to give the boas a sense of security / privacy.
Try a different male or female, maybe your boa(s) isn't ready to breed.
Don't be discouraged if it doesn't work out the first time. They will probably be in better shape next season, there is only so much you can do and then it is up to the boas.
Take some shed skin from a female you know is producing the breeding pheromone and soak it in hot water, to make a tea type spray you can spray on a female that is not getting the attention you were hoping she would. It will make the male think she is the female that's ready to breed and he will get to courting. Yes this works I have tried it!
If the female is not ready and not willing you really will just have to wait, a male can stimulate her to get her follicles growing, but sometimes it's like putting the cart before the horse...LOL...
Is my female gravid?
Is she basking a lot?
Does she look bigger in the rear half of her body?
Is she cranky ?
Does she have less of an appetite or none at all?
Check her temp with a temp gun, gravid females are warmer than non gravid females usually 86-90 gravid vs 84-80 non gravid average.